There should have been wires plugged into the fake tweeters, also with the pioneers they are very stiff to get in.
The tweeters actually clip into the hole and that's where it gets stuck rather than them being too deep.
Try slotting them in and out without the grills a few times just to loosen it up then try it with the grill, it still requires some pressure and I can't say I'm 100% confident mine are in fully either still.