Here’s the story from what I’m able to gather:
Uncle Scrooge admits he’s gay, and so does Donald. They have sex and Donald’s testicles fall off. They continue to have sex, then Donald Duck leaves his house to talk a walk, then he is seen having a gun while spinning around for some reason. Donald’s face also seems to imply he’s about to do something malicious, possibly at Uncle Scrooge, since he’s the reason Donald no longer has testicles.