It won't hurt anything to store out-of-level, especially if your refrigerator is turned off.
You did not say if you were out of level front-to-back, or side-to-side. If front to back, you should be able to block up the tongue jack to make the front higher, or drop the tongue completely to the ground to make it shorter. If it still needs to go shorter, you can block up both wheels, which will raise the camper higher so the tongue can be lowered even more.
If you are unlevel side-to-side, can you block up one side under the wheels to bring it more level? I think the highest I ever had one set of wheels up on blocks higher than the other side was 10 inches at a campground once. It looked scary as can be, but I had really long boards stacked up on top of each other, each one a little shorter than the other so they formed a wedge I could roll up on. But my wife yelled her head off when both tires made it to the top so I wouldn't roll of the back of those boards! When I had it all in place, I chocked everything, put the jacks down really tight. Maybe you could the same.