Are there other possibilities?
Yes.
Guys, I know this story sounds really bizarre so far. A diver missing since Wed, isn't noticed til Friday. Body unable to be located by several search teams. Indications that an untrained diver has made it to a part of the cave that some very good divers are having difficulty with.
But please keep in mind that these searchers are using caution and judgment on where they are searching, which a panicked diver with no training and determined to get out would not have had.
I have every indication that there is a lot more information on specific details, we're just waiting for those involved to tell their part.