doesnt sound like your problem is that huge.

adjust your hub, make sure the locknut is secured tightly against the cones. a perfect adjustment doesnt matter at this point. grease you axle threads and spin the axle nuts to spread the grease.

put your wheel back in the frame, and tighten the unseized axle nut, thus half securing the wheel to the bike. now your bike has become an axle vise. now if you're lucky you may be able to get that seized nut past the messy part.

what to do next? i dunno it depends on you effed you ***** is!