Front Bumper can't come off without your hood up. What is exactly wrong? Do you pull the lever and nothing happens? Is there resistance?
Try jacking up the Drivers-Front side and taking off the wheel. Along the upper part of the fender, there will be black sheathed cable that comes out, that's one access point to trying to open it. Make sure that this is still good and not torn or ripped.
If you can, lift the whole car up and take as much of the front bumper off the bottom of the lower radiator support. Peel it back and try to reach the cable where it connects to the latch and pull it.
I'm not sure exactly what is going on with your car, but those are a couple of things I've done to open stuck hoods.
