On a door warped like that you'll most likely not be able to soak/bend and expect it to stay that way but for what it's worth, it's warped in a good direction...
if you want to try a small project (and really, you have nothing to lose?)
There's a tool called a Japanese Dovetail saw (there great to have around especially if you're a modder)...it's a "saw" version of a bread knife...they're super thin and sharp!...what you can do is lay down your door curve up, using a metal ruler as a guide, cut slots length wise about a 1/4" apart (closer together at the worst of the curve) in the back of the door, you may have to temporarily remove the magnet . Cut until you're about 3/4's of the way through (keep the outside face pretty

)...what you're doing is basically making relief cuts which will allow you to bend the door back...
Mix up some good 2 part clear epoxy and smear it into the cuts, place a piece of wax paper on the glue side (very important step

), then clamp it between two pieces of flat wood and let cure, sand/clean up.
The door will be narrower than stock and will move about but it'll be flat...worst case, like Turbo said...make a new door (or maybe Rob has something kicking around)