Not that solving the case will change anything, but, I need to know. What I will say is this. This boat is different than my old one. Each time I splash her, the water comes over the transom until she's level in the water. Mike, Jim's friend, explained to me a while back that Jim had relocated the batteries and was unable to put the poling platform on due to the stern weight.
This boat has a 175 HPDI on it, a little bigger than my 150. It also has a Bob's Jack Plate on it, which adds another 60 pounds plus. Again, my brothers synopsis of what happened works. Push down on the stern, up comes the trailer tongue like an A frame, and the truck jumps the chock, and into the water the truck went.