iPhone 6 Vibrator
iPhone 6 Logic Board
A picture of what the dental pick is poking at would be useful inside the back case. If you get on the wrong side of the frame rail you can break the ear where the screw goes pretty easily with that pick (yes it appears to be titanium). Guess that is why only the plastic pick was part of the toolset, but used a metal one as depicted and ran into this. As you say this is challenging, and more pictures are better.