Hi,
I spent about 48 hours trying to solve this problem...
What I did is I took out the camera connector hidden behind a black tape near top front camera.
After that I tried the restore mode.
And it worked to full complete.
I tried to put the camera connector back in after the full reset, and it went to loop again.
It seems taking out the camera connector solves the problem.
A full working iPad with no front Camera is my solution.
Try them