Coolant problem, I have been having to add coolant every 2-3 days?

Well, the techs at the dealership are most likely flat rate, so they only get paid so much for each job they do, and probably only a certain amount of time for diagnostics, so I don't think it's that they are lazy or lack knowledge, it's just that they can't spend all day on something if they are only going to get paid 1 hour for diags. Dealerships differ in how they pay their guys for diagnostics. But before you go purchase the EGR cooler, let me see if I can break down these replacement diagrams, and see if you could check inside the actual cooler pipe for any signs of coolant, I'd feel terrible if you replaced a $450.00 part and that doesn't fix your issue. I thought the dealership would have possibly checked inside of it or inside the exhaust manifold when they had the engine out. That would be the logical thing to do, but since the EGR cooler is there to cool the exhaust gases being sent into the intake when needed, it looks like the coolant is pumped around the EGR tube to cool the exhaust which makes sense.

You could unbolt this tube running to the bottom of the exhaust manifold, and leave it off over night and see if any coolant is leaking out of it, thats the end of the EGR cooler, so if coolant is leaking into the exhaust, it might be at that end, especially since its the lower section.

No, you can't run the vehicle with that EGR pipe off, because it will be like a big hole in the exhaust. I was just suggesting that section for one, because you can get to it, and it's the lowest section of the EGR cooler. So, if coolant is puddling up or leaking out of the cooler jacket it should show up there. and after I posted that, I had another tech message me the same thing, "check the EGR cooler because they can leak inside." If you have thick gloves to where you can remove that pipe after the vehicle cools off a little, or you can just take it off and let it sit and see if anything drips out overnight.
There looks to be 2 bolts on the outer pipe that's attached to the exhaust manifold, and then there are 2 nuts with studs that bolt to the Cooler itself.
If you ran the vehicle with that pipe off it would be so loud and it would also affect the oxygen sensors, so that wouldn't work. The only real options are to remove it hot or cold and let it sit. If you're going through that much coolant, I think you should see it dripping if that's the issue.
Or the last option is to pressurize the system with that pipe off, that will act the same as if the engine were running with 15-18PSI of pressure. If it's cracked inside and opening up when it's hot, it should still leak with a pressure kit on the radiator opening.

Here's the guide to pressure testing:

https://www.2carpros.com/articles/radiator-pressure-test

It's difficult to see what you're seeing there. I do see the dye.
Is this the same bolt as in your video? I can't tell if you're looking at the EGR possibly by the side. Are you meaning the head gasket leak coolant out externally onto the EGR tube? If so. I would hope it wouldn't considering how many times it has been replaced. That being said, yes it possible for head gaskets to leak externally.
Although looking at the video a couple of times, that looks like you're looking directly down at the cooler tube and that bolt is the upper bolt for the cooler to EGR tube. The cooling hoses above that and below it is where the coolant is circulated around the EGR tube, cooling off the exhaust gases before they reach the EGR valve.

I'm glad to help, this is a tough one, but I do now see liquid coolant there on top of the cooler. So, the problem is getting worse.
Almost looks like it's starting to seep out of the top of it now. And I'll bet that thing has been taken apart a bunch of times.

Sorry for all my wonderful artwork but check to see if that EGR tube has coolant running down on the underside of it, if it's not too hot. I didn't see anything in the video from the hoses above it, although I could have missed something.

I think if anything, it's leaking probably out of the top of the cooler, and then probably into the tube right where it bolts up there. So here is what you need to do: when it has cooled off, unbolt the EGR tube from the EGR valve, and check that flange you mentioned where it bolts up, check for any cracks where it's leaking out and most likely internal as well. I think you're on the right track there. That tube will have gaskets on either end that will need to be replaced but let's find our leak there first.
The torque specs for those bolts are 13-17 ft lbs.

That entire assembly the EGR valve is bolted to is that Water Temperature Control Assembly, the 1st picture is from the back side of the Temp Control assembly, and the 2nd picture is from the front, that tube above the EGR tube in my last post is also a coolant pipe, it just doesn't have its rubber hose attached to it, but you would notice more coolant on the ground if it was coming from any external cooling lines. So, we want to be 100% sure of what's leaking, especially with a $450.00 part.

Yes, you are thinking the same thing I am, she's hearing the gurgling from the air that's getting into the heater core and running through the dash. Thats just because coolant is leaving the cooling system and air is being drawn in. Once you pull that EGR tube we should have a much better idea of how it leaking. But it's almost good that it got a little worse there, it gives more reason to pull the EGR tube for inspection. You mentioned the exhaust having some extra steam, so the coolant is running right into the exhaust manifold it appears. You might not always notice the water exiting the exhaust too when the electric motor is doing the work.

Hello, did you happen to find the leak? Were we in the correct location?

I would at least up bolt that top part where we saw the drip of coolant sitting, there's only 2 bolts there. Just to verify that's really the section of the cooler you need. If coolant starts coming out once you unbolt that, you know what's up. Then just tighten the bolts back up. I looked through All Data but could not find a part number for it, which is not surprising.

If possible, can you identify this as the correct part number, you can call the dealership and just tell them you may need the part and want to verify the correct part number by your vin# and let them know you'll get back to them. I found one for extremely cheap price, made in China, I'm going to search a couple other places for a part number. It's possible if this thing is just cracked somewhere, to find someone that could maybe weld a bead over the crack depending on where it is.

This is something I think you may be able to get out without having to remove the manifold, if you take it out from underneath. I'm a big fan of saving money wherever possible. The gaskets I think you will need to get from the dealership, we don't want them to leak. But they shouldnt be too much, you can ask the dealer on those if you call for the correct part number.

I'm not against you buying a less expensive one, I understand how these things go. That was the whole reason I became a tech to begin with, to save money and fix my own vehicles. I'm thinking a weld cracked right around this top ring here where the internal pipe is inserted. I see one on here for about 140, same part number I'm seeing at other locations on that year and model. I would confirm the issue though. After all this, even if you just unbolt the bottom section that goes into the manifold, you should see coolant drip out without even having to fully remove the bolts.
Even this super cheap one is listing the same part number, you could also call around to some used parts yards and see if there's a wrecked vehicle to take one off of. I wouldn't spend $500.00 on this either. So, a few options to think about.
But let us know of the outcome, if this is the problem, it will help others in the future if we see this again.