chris

Yes, you have fried the rear camera. it should be removed as very sensitive to heat.

i belive it should work without cameras, the X does.

if you click the i at the bottom right corner it should display serial and imei number, if there is no imei then it will need a new Baseband chip (i think).

Have a try but I doubt it will work.

You`ve broken the Digitizer, you will need a new screen.

Yes, just be sure to keep the homebutton and Taptic with the mobo.

if the homebutton is super sensitive then its usually the flex on the actual homebutton that is damaged.(usually from opening the phone wrong). Also check the flex on the screen, its the smaller connector that is responsible for the home button and is easily ripped where it bends through 180deg.

its paired to the board so true tone will vanish

I take it you have proven this display is fully working?

I would try a different screen.