temporarily, you can use the emergency release for the front trunk. If you have relocated it to the tow hook hole, it'll be easy. If not, look/reach up for it thru the radiator opening - it'll be taped near/under the right headlight housing. The other access for it is in the right front wheel well. It's a steel braided cable about 1/16" thick.
Sounds like your problem might be the lock/actuator in the lever housing. IIRC, and you have a small screwdriver (#0 or #1) w/ a 2" long shaft, you can try and slide it in between the trunk levers. There, you should see a white plastic 'bar' - try to slide it out of the way or push it down (I can't remember exactly which) to unlock the lever.
Bottom line, I think you'll need to take the lever housing out and replace the actuator (
See Part #7 Here ). This is probably not the correct part # for your MY so I'd pull the one you have to get it. Of course, puller the housing requires pulling the drivers seat out too (to get access to the screws) if I'm not mistaken.
Good luck!