Ipad 2 no life after repair

I replaced the battery in my ipad 2. After I replaced it my rear camera was not working. I tried replacing the camera. no help. Then tried replacing the board between the two camera. No help. I thought I would put it back together and use it without the rear camera. After I put it back together the Ipad is completely dead.

Tried reset, Tookout the mother board to unplug the battery for a few hours, Pluged into Itunes did not recognize. Still dead. Can anyone help?