If electrical, I'd pull apart ANY e-connection under the cowling and would clean them up, re-apply dielectric grease and then re-assemble. I have seen shorts in these connectors before, on all makes and HP motors, but perhaps it could be 'opening' on the shock of the landing.
You know ... if you have WING NUTS on your batteries ... do me, you, and Sea Tow a favor and THROW then AWAY. Replace with nylok fasteners AND put a stainless steel split-lock washer onto each post 1st, then put the main motor connections, and then an internal or external-toothed washer between any other lead placed to the battery post. Use a std split lock washer if/as needed, sometimes the toothed-ones are tough to find.
If indeed water into the carbs ... the loose hose would have to be behind or under the air silencer, or positioned that it dumped quite a bit of water in immediately. Still a good thing to check!