Ok, as promised, here is the update on the bags/tent bag issue:
It seems that the dealership that my bike store goes through got some "erroneous" bags. They (the dealership) offered to replace my 60L bags with 45L bags (umm.. no); so I instead opted to wait for the RMA process from Axiom. The bags came in today, I have them mounted, and the bags have the correct clips; so all is well on that end.
The issue still remains where the clips that the bag system uses is too small and prone to unsnapping. My current resolution to this issue is to loop a bungee cord from the rear of the (rear) rack, around the tent bag, through the pannier bottom loop (I may instead route through the top loop), and then to the front of the rear rack. It seems stable, though I'm going to test it out this weekend to confirm. Since bungee's are elastic, I may also end up going with my original quick-fix; which was to use a strap to secure it, we'll see.