Well, certainly a rather unique way of organizing code, oh dear, anyway.
was it ever working ? what was the last thing you changed that broke it ?
(and full disclosure, I have not tried to run it and see what’s happening).
I assume you have read this, second time today I’ve linked to to this old topic.
first red flag is event handers registered in usercontrol, every time usercontrol is called you register a further set of handlers.