

Stopping it eating or drinking would involve being a constant low grade threat that it has to spend time and energy monitoring. Gorillas normally live in groups which means that while one is on lookout duty the others can feed in peace. A single gorilla being constantly harassed by what is comparatively huge group of humans would find itself in a constant state of fight-or-flight.
If the humans were ineffective at stopping it drinking in particular, or finding hydrating food, the contest could end up going on for a very long time.
Obviously, a lot depends on the exact rules and location of the encounter. If it’s in the gorilla’s prefered forests and the humans can’t use the environment, it’ll be a stalemate. If it’s somewhere enclosed, so the humans can’t escape, the gorilla wins. If it’s somewhere reasonably open, with less food, the humans could wear the gorilla down. If both sides can use the environment it swings it further towards the humans by overwhealming numbers throwing things.
Nah, I’m going with it dieing of a combination of shock and embarrasment. That is not how a snake bite is supposed to go.
If the kid’s first reaction to somerhing deadly is chomp, I pity anyone who crosses them in the future. I don’t think it would be inappropriate for them to wear the fangs as a trophy, and a warning.