You probably know this however 1. On a manual transmission the switch has to be OFF or in Accessory; 2. on an automatic transmission the transmission has to be in PARK, before the remote trunk release will operate.
Also this might be helpful, In the fuse block under the hood,
Fuse number 26 is labeled Door Locks.
Relay number 32 is labeled Retained Accessory Power (RAP)
The fuse block inside the car,
There is a fuse called in my book as TRUNK/HTD SEATS for heated seats. These fuses are not numbered in my book but the fuse is just below the AIR PUMP relay near the top left row of fuses. That's the only fuses that I can find in the book that may relate.
Do you have keyless entry and does it open with the remote? If it does my guess is the switch on the button itself. I hear it clicking when I press mine. I doubt the relay under the head will have anything wrong. And the fuse under the hood also operates the doors.
Hope this is some help. Good luck.