The same thing happened to me today. The charger tip broke off and got stuck in my iPad. I used one of the tiniest drill bits I have (for jewelry making). I slowly and carefully screwed it into the stuck piece by hand. (I screwed it in a bit diagonally.) And I pulled it up, and the tip came out without much resistance, thankfully.
Before trying the drill bit, I tried one of my tweezers, a safety pin and a push pin. The tweezers were a bit too big for the opening. The safety pin was too big to go in. The push pin couldn't really go into the stuck tip piece.
If you have a tiny drill bit, that may be your best bet.