Generally in aluminum parts in aerospace, locking stainless steel threads inserts (“helicoils”) are added for pullout strength, repairability, reducing risk of damage when fastening multiple times and to meet the requirement (which almost always exists) for secondary back-off prevention (primary is usually controlled preload). The locking feature is 1-2 threads in the insert that are deformed to provide a decent amount of friction even if preload is lost. But for a special case like this it’s possible a unique design was used; I would be interested to read about it.

From the images, it’s not clear which fasteners are removed but if the issue is not access it could be a stuck fastener for whatever reason and maybe a rounded head. I wouldn’t be surprised if nothing is damaged but the procedure was stopped due to higher than expected torque, and they are taking it slow to decide how to proceed.