Replaced power/volume cable and now the LCD won't start up?

During a routine Digi replacement my coworker cut the power/volume cable. After replacing the cable and the Digi the iPad begins the start up process and then goes black. After that I get nothing. I have replaced the power/volume cable again, diconnected the battery, tried an alternate LCD etc and nothing works. I cannot get it to sync with iTunes to do a DFU reset because it requires you to acknowledge it on the iPad which I obviously cannot do. It is not a back light issue because there is nothing to be seen under direct light. When I plug it in to a power source I can hear the sound so I know that there is power but I get nothing but a black LCD. I am at a loss.