I recently replaced the back hatch/liftgate latch assembly on my 2014 and thought I would document it somewhere. It was stuck locked, and the only thread about such an issue on here was completely unhelpful. My closest repair shop wanted $300 before even looking at it, I was able to do it for $84 in about an hour.
The latch assembly is behind a cloth-covered plate on the inside. It's held in place with plastic pegs which can be pulled out with a claw hammer. I didn't see a way to keep these intact reliably, so a different way of putting it back on will be needed at the end.
Because the assembly is bolted in on the bottom, the hatch needs to be open before removing it.
This image is of the back of the assembly. To open the hatch, slide a screwdriver down behind the assembly next to the handle arm and push this metal piece to the left:
While holding it there, shove another (preferably flathead) screwdriver into the side of the latch itself:
Then push and it should open.
The only things holding it in place are a cable, the handle, and 3 bolts. The cable is a bit tricky to unplug since it has a plastic clip keeping it in place, a screwdriver can help. Push the handle connector out of the loop it's in, remove the bolts, and it'll slide up and out. Then simply put the new one in, and remember to plug in the cable.
For anyone else stuck putting groceries in the back seat, I hope this helps!
PS Mods, I think this counts as body/exterior but please move if needed