edit rereading your original post, i think it might take someone a little better at the event system than me to help.
The form raising the event is ignorant of the receiver - the receiving party is the one attaching a listener. It could call a method on the form, but that surely would involve polling?
I think I might not be understanding your use case, my apologies if that is so, but are you looking for a “global” event system? Something like this maybe :
edit 2
Yeah, I definitely misunderstood what you were getting at, sorry.