I am trying to run a wire from the hatchback to the front (rear dashcam), and I can't seem to be able to remove the little plastic covers to get the grab handles off (without doing too much cosmetic damage). How do I remove these things so I can route the wire through the headliner, and then reinstall them?
Not sure if they used the same handles in your car that they put in mine, but if they are: Use a bit of string and ballast to hold the handle down against its return spring. Then look at the hinge-ends of the handle- there should be two plastic covers to pry off. Mine have little keyways to get a screwdriver or prybar started. Once the covers are popped off you'll find capscrew fasteners making the structural connection to the roof- back them out, catch the falling parts and (eventually) reverse for reassembly.
This is what mine look like. I've tried with a screwdriver in the little notches, but there does not seem to be any latches released
I don't think the mechanism qualifies as a latch. Heck, it's a stretch to use the word 'mechanism.' AFAIK there isn't really a latch, the keyway is to let you put enough tension on the covers to cause them to deform and stretch slightly, so that they pop off of the handle hinge bases. More like popping a bottlecap than unlocking a deadbolt.