For the pop biscuits, that's fine and you don't need permission for it since it's just making treats between characters.

We like the idea of a dueling tournament! We might have different dates, but it sounds like fun!

We'd need to work out some of the details for the Poltergeist idea. Like who the actual culprit would be, who would be administering these pranks ICly and OOCly, as well as how inclusive the event might be? Essentially, it needs more foundation. We can keep it in mind for the future, though!