There is a wired level sensor toward the rear of your RV. Usually on the last crossmember behind the tires. You can view the Lippert website for pics and details. I would check these wires. Also any other wires in the area that may have been stretched when the tank fell. May have a weak ground or short.
I would think the hydraulic lines are fine if there are no kinks and no leakage. Highly doubt the lines are part of the problem.
Also, make sure your battery is fully charged. We usually also hook up the TV, shore, or generator when operation the hydraulics to help the battery via the converter. These systems take a lot of juice, and if not available, it plays havoc with fuses.
Also, it might be the fuse itself. They do wear out. My unit is seven years old and I have replaced all the resettable fuses (auto and otherwise). They are cheap, so an easy test for your problem.
Scott and Liz - Southern NM
2012 Wildcat Sterling 32RL - w/level up (best option ever)
2007 Chevy 2500HD 4dr short bed Duramax w/allison
Reese Fifth Airborne air ride king pin coupler with Sidewinder