Can anybody explain more how to do this? My key won't open the trunk and i've been very unsuccessful to reach for those straps behind the rear seats.

I'm not certain since I don't even have that trim or rear seats anymore but IIRC you can pry on the trim around the posts above the seat and get the posts pulled up. You can try getting someone with small hands to jam their hand in the side to try to reach the strap too

Sent from my XT1575 using Tapatalk