2016 T&C - OBD code P076a
 

I have a 2016 Chrysler Town and Country V6, 3.6 Liter under 60,000 miles.

Came home from a trip, 2hour drive, all was well. Wife went to work with van and kid and said oil pressure went up and down and then into limp mode where it would not go over 30. She made it home as she was not far away. Tried moving the car and it was clunky putting the van into gear both forward and reverse.
Car was towed to one local mechanic he said the OBD code was P076a. He thought to fix problem by replacing Transmission solenoid pressure switch assembly. about $850 pre tax
Had it then towed to local dealer and they want to fix problem by replacing the transmission valve body and new filter, some sealer? and fluids. about $1650 pre tax
Both seem not very confident in the diagnosis (which cost $100 and $180 respectively)

I am inclined to go with the dealer because they see this kind of vehicle often and will ask if their cost includes replacing the transmission solenoid switch assembly as well. However from my 5minutes of amateur level "googling" replacing Transmission solenoid pressure switch assembly seems most likely.

My worry is that there is some foreign or stray metal in the transmission case.
Anybody care to share some thoughts?