The Missing Rivets:
I have trouble understanding why all the smaller rivets are missing and the artifact shows no damage around the rivet holes. If the piece is blown off the aircraft frame (or off stiffeners), and there is no damage from rivet pull-through on the artifact, then every single rivet must have instantaneously reverted to nearly its original diameter, pulled through the frame, and fallen off. This seems somehow unlikely to me.
Why should the rivet pull through the frame, when the artifact must have been the lighter gauge material? Is the non-factory end of the rivet so much weaker - how does that align with the overall design strength for the rivets, which would mandate a rivet design where the two ends have near equal strength?
Is it possible that we are not looking at holes for rivets used on aircraft skin, but for some other use, where another rivet type (like a split head rather than a compressed head) may have been used?
Or that the holes were not for rivets at all, but rather for something else (tacks, nails, screws, thread, ventilation, RF, light, glue, etc.)? I've drilled plenty of 3/32 holes in my days for things other than rivets.
Jon