[Rich]

If you get it running, run the engine to get it totally up to temperature, more than once, then change the oil. Do this a couple of times.

If any of the wiring, electronics, etc. got wet, it will start to become a problem as things start to corrode. Luckily you're in fresh water, but it can still occur.

See how the dealer warrany will handle this, as it sank due to a faulty carbon ring. I would think they should be totally responsible for this, includnig an extended warranty to ensure that failures or issues in the future as things corrode won't stick you with a lemon.

Good luck!