I changed the backup bulbs in my wife's Rogue Sport to LED's as well. I found a video on YouTube for Nissan Qashqai backup lights and it was the same. Open the hatch, there is one screw on the right side that you have to remove (the handle area where you may put your hand to close it) and then the were a few plastic retainers to remove then I stuck my hand in the area for the handle and started pressing down to force the clips to let go. Every time one popped loose, it sounded like something was breaking but after getting the whole cover off, nothing was broken and it gave access to the bulbs. Hope that helps.
I bought a car, and it turned out to be an alien robot. Who knew?