Stripped head off of license plate bolt... How to access interior bolt placement

Hey everyone, new to the forums. I'm a long time viewer, having gained valuable information from these forums.

I'll cut to the chase — like the title says, I stripped the head off of one of the license plate bolts. I tried removing the interior liftgate trim. After inspection, it looks like the carbon fiber is blocking the area where the license plate screws are located.

I removed the liftgate button to see if I could get an angle on the screws... No luck...

At this point, I've been using bolt extractors to try to drill the sucker out, but the broken bolt seems to be completely seized

If anyone has any advice on how to access the interior location for the license plate bolt housing, I would be eternally grateful