Larger version of the photo here:
https://i0.wp.com/www.transponder120...ze=1000%2C1268
The countersinks are clearly visible, so we're not looking at screws that have pulled though.
I'd be looking at when the panel was last removed (presumably on a maintenance check) and examining the possibility that the wrong size of fastener was used to reattach it.
At least it wasn't a windscreen ...