Hello, My name I Randall. I will do my best to assist you with your question.

thats a tough question. Its sounds like a relationship of water and charging system

However, it could have just failed

I would first try charging the battery. I would remove the battery terminal;s and be sure very clean, these tyep termianls are known to lose connections at times

Cahrge the battery or jump it for say 1/2 hour to ghive good charge to battery then let it maybe sit and dry down for a bit. Possible it will come back working

Everyhting you have described leans to charging problem which yes caould be the battery termianls, battery or the alternator or more rare conditions, the computer

I would do the basics. get those termiansl off, cleaned, wiggeled back on while tightening, get the battery back to charged state as when under say 60% battery charge, the alternator may not kick in

Other than this? need a pasrts store or shop to run charging test