If yours is a normal electric landing gear, which it sounds like, the motor drives a cross shaft through a gearbox. The cross shaft in turn drives a set of bevel gears in each leg, which rotate a screw which does the actual raising and lowering of the legs.
It sounds like your bevel gears are either badly worn and not engaging fully, or have a broken tooth or two. The chances of the trailer dropping are basically nil since the screw won't turn just with gravity. However I think you're justifiably worried about it not working at some point.
If you pop top cover off the leg there will be info about the legs inside the cover.
It's pretty normal for the motor to move around since it isn't securely mounted, so it can flex without breaking anything. A very poor system.
My curbside leg was also very difficult to access, but where there's a will there's a way. There was just enough room on top of the generator housing to work on the leg. A bit of a squeeze, but it could be done.
You have two steps: locate which leg is popping and jumping. It could be both legs because it could be the gearbox driven by the motor that is bad. You need to locate the problem. There are replacement parts for the gearbox and bevel gears. You can fix those, or you can buy replacement legs like the Bulldog system.
I replaced my legs with the Bulldog system because I was very tired of the sloooow raising of my trailer, and I had to either fix the OEM legs or replace them.
Good luck.
