Low power when accelerating

This is my wife's second vehicle and if it is like the first, I don't think I will keep it.

Started with a shuddering problem when accelerating. Only above 60mph. Now it doesn't shudder, it just acts as though it is not getting fuel, even though the gas pedal is being pressed. It happens above 30mph at roughly 2,500rpm's. So, I take off from a stop light, all is well, it flips into 3rd or 4th gear, and now it acts like I completely let off the gas, even though I am slowly increasing the gas to get up to speed. If you slam your foot down, it cycles through properly and no issues. Note: There has not been a single code thrown for this engine.

Now, because of the first expedition we owned, I was aware of Ford's notoriety with coils. Therefore, I took it into the shop and had them replace 4 of the 8 coils. Problem still persists. I take it back to the shop, they tell me it has something to do with the transmission. I take it to a transmission shop and they tell me it has something to do with camshaft actuator and that it needs to go back to the regular shop.

After doing some research, it would appear that replacing the camshaft actuator is possibly a very lengthy and expensive process. Having already dropped almost $500.00 of the 4 coils, I am not very keen on dropping another $1,000.00 to see if it is the actuator.

All of that, to ask, is there a way to be certain of the issue before replacing big things like this, even though there are no codes?