Rear side airbag not attaching correctly

I had the rear seats folded and was storing stuff in the boot while holding to the side airbag part, applying a force directed from outside to inside the car, and it came loose at the top.

Figure to showcase the part i'm refering to:

Attachment at the top seems to work by a plastic part which first goes into the elliptic hole in the sheet metal, then slides down into the slot below:

Attachment at the bottom works by a slotted metal bracket mating to a threaded stud on floor (highlighted in pink, stud not visible), and a U shaped rod sliding down into the sheet metal U (highlighted in blue):

I've tried to put it back together by putting the plastic bit in the elliptic hole, lining up the 2 bottom attachment points to where they mate, and sliding the whole part down, but the top attachment point never seems to slide down into the slot enough become really secure, and touching the part is enough to make it slide up and out of the slot.

I believe the issue here is in the manufacturing tolerance, where the 2 bottom connectors are bottoming out before the top connector fully slides down into the slot enough to become secure, which also explains how it came loose in the first place just by holding on to it.

I'm thinking I can 3D print a new plastic part such that it sits further down, and hopefully becomes fully engaged in the slot before the the other 2 mounting points bottom out.

I think I got the diagnostic and solution figured out, but I'm posting this in case I'm doing something wrong, and hopefully someone will correct me.

Here's a video to help make sense of the pictures:

Edited 31 August, 202531 Aug by c_radicallis