Q: I have replaced an ecm on a Sentra and I am not sure if it is compatible

I had to rebuild the engine in my daughter's car. While engine was ought, hood was off, tarp blew off and ECM was sitting in water. When I reinstalled the engine I didn't think anything about the ecm, it was dry then but I was not able to get the throttle to act correctly and it kept losing the program. The car has run probably 4 or 5 hours altogether and the last time it ran the tachometer faded to zero and it died. Have removed the ECM and heard water sloshing so I took it apart. As chip that was in the water has a burnt spot. I ordered off the internet and received the wrong ECM. My ECM is a mec950-190 and they sent me mec950-340. I did not figure it would work at all. All the accessories work, I can teach the throttle position sensor but it will not start. The tachometer does register the starting revolution s. Will this ECM be able to be programmed to the car. I have tested for spark and it is not firing. Will not start with starter fluid either.

My car has 133000 miles.
My car has an automatic transmission.