If you do wind up throwing parts at it, please use quality ones
Or don't bother, you'll waste time and money
The TCC code is the only one that's a wildcard, I'd clear codes and put it through a drive cycle to see how long it takes to come back
As for the thermostat, a non OE was the first mistake
If you can get it through a drive cycle and inspected, maybe take that as a sign that it's on a 12 month death march
It doesn't owe you anything at that mileage
Has the transmission fluid ever been servic