Do those cars have a real time MPG thing that says if it's in V8 or V4 mode? Maybe that's just a truck thing.

Otherwise I don't see anything in the tune that says tap shift disables the DoD. It says it's active in 3rd and 4th gear no matter what but the transmission files does not specify if the TUTD paddles disables anything.

Pulling the oil pressure switch connector is fine to test, the system will disable if the switch in unplugged.