Oh, then you just need to find a way to lure Hamlet into room 6 and from there drop some liquid poop into the lock so it breaks, leaving Hamlet and the donkey inside. I suggest you then go as far away as possible since strange, annoying and probably pretty green things will start to happen.
But keeping a distant should help
. Then to trigger some time to pass, move in and out of the cellars 6891 times and you should be able to see some invisible donkey babys taking a bath in the blood at the fountain, with Hamlet standing there as a proud mother and the donkey unfortunately dead (since invisible donkey birth is brutal).
It might almost be quite not like a not alternate ending
.