The Serpentine belt came off while driving, after replacing the belt, the belt still rides off to the side of the belt tensioner pulley?

Hello, I have a diagram pulled up of the drive belt for your vehicle and will post it, but if you're looking directly down in line with the belt and harmonic balancer, is the balancer the only pulley that looks out of line with everything else? And also does that type of harmonic balancer have a rubber strip in between the pulley section and the inner section of the balancer? Most are made with a rubber ring around the inside to help with engine vibrations from the crankshaft. I'm wondering if that rubber ring has broken free in some places and now the outer ring of the balancer is out of alignment. Can you take a picture and post it here?
The 2nd diagram below is what might have happened to the harmonic balancer. Does it look like this?
If this turns out to be the issue and you don't have the correct tools to pull the harmonic balancer off, AutoZone and other parts stores will rent the tools out to you. You have to give them money to cover the cost of the tool if it gets stolen, but at least at AutoZone I know they will give you all your money back after you return it, so really it's a free rental.

https://www.2carpros.com/articles/how-a-harmonic-balancer-works

I do see the belt being off the tensioner quite a bit. I know it's a pain, but I would take the belt back off, and if you still have the old tensioner, you could compare the two and make sure they gave you the correct part number. Do you still have the box it came in or the part number of the new one installed? I can try to cross check the numbers and see if it's correct.
If you don't mind taking the belt off again, I would check the alignment of crank pulley to the rest of the pulleys, use something real straight to check them. If the crank pulley has broken the rubber section, the outer section of the pulley you should be able to rotate it or move it around by hand. You'll notice if it's broken. Especially if it has moved out that much. I have the OEM part number here, it's 12563084. I will look up some aftermarket numbers too.
Where did you buy the tensioner?

Well, that aftermarket number seems correct, do you still have the old tensioner? These are the interchange OEM part numbers I found. But the Delco 38353 is correct in some aftermarket locations.

Okay, then there has to be one of the other pulleys is off, it's difficult to see exactly from the pictures, this is the only section of the harmonic balancer I see off somewhat, Thats the trigger wheel for the crankshaft position sensor I think I see behind the pulley there. Somethings definitely not right there, the belt shouldn't be that far off the tensioner pulley. Take that belt off and check all the pulleys to make sure there isn't anything out of place. Is the Alternator bracket broken anywhere? It can really only be the Alternator pulley or Balancer pulley that would put the belt off some much like that.

There looks like there are a couple different setups/designs for this vehicle. I am coming across other people with the same issue with this vehicle, the belt is hanging over the tensioner exactly like yours is. Is the diagram below the correct routing for your engine?

It's difficult to tell from the angle if you can get your hands on the crank pulley and give it a good shake to see if the rubber ring has broken free. In this photo it almost looks like the AC compressor is in further. That trigger wheel I circled in purple is attached to the inside of the crank pulley and that triggers the crank position sensor, so it's in the right position or the car wouldn't start. But it can only be a few possibilities, like the Alternator Bracket (which I have seen crack before and was only holding the Alternator on by one bolt), that outer crank pulley or the incorrect tensioner. I know those crank pulleys do break the rubber section apart like the photos I posted. I mean that one is an extreme case, it's actually missing the rubber section that would be holding the center section to the outer pulley ring. Really the best thing to do is to pull the belt back off and check everything. Because whatever is causing this will eventually break and leave you stranded somewhere. I can see that belt coming off too,
One of the pulleys has to stick out at least a 1/2in more than the rest for the belt to be so far off the tensioner. I just don't want to see you get stuck somewhere. The Alternator bracket is pretty tall, so if there's a bolt on there that is not tightened all the way in on the lower section, which will cause it to pivot out up top.