I think the panel was still ok after I tested it. I suspect the GPU/LVDS just weren't calibrated to run it. I'm no expert on the intricacies of LCD data signals though.

As for sourcing the LVDS cable, the same applies - go to a service centre and ask. Again, you will be chopping off the USB part for the camera so a failed of damaged one may be allright for your purposes. USB is not as sensitive to cable quality as LVDS so that may also help.

Essentially what you will be doing is using the camera connector chopped off the LVDS cable and extending it to reach an internal USB.
To get a free internal USB without Removing bluetooth, the only way I can think of is to wire a USB hub to the logic board in its place, then wire the bluetooth and the iSight to the hub )maybe a GPS while you're at it).
In order to get a hub to fit in the case, you can either design one yourself by tracking down an appropriate and compatible controller chip, or simply find the smallest one you can off the shelf and unsolder the USB ports.