Dear Sunken,
This is my first post on this site, but I'm certainly not new to watercraft but I'll try to help.
If its insured, call insurance co and let them deal with it. If it was completely submerged, water is everywhere....air intake, supercharger, intercooler, engine, electronics, ....etc. Not worth the hassle.
If its not insured, which would be a lesson in itself,
1. It needs to dry out..and definitely use an air compressor and vaccuum to remove water from air intake, supercharger, intercooler, engine, electronics, ....etc.
2. Keep oil in it
3. If after a few days of being completely dry, it still doesn't fire, it could be any one or combo of 100 things and you could chase them for a long time. Power train and electronics would need to be torn down and put back together.
Before you try to revive it too much, I would move down the insurance route as you wouldn't want any of the work you do to violate the terms of your policy.
Good Luck and I hope mine never sinks.