If you cannot get it repaired, try unplugging the feed wire from the camper on each jack. Then use the drill to raise and lower ... if you don't unplug it, you're raising and lowering, AND probably spinning the dead motor as well.
You may also be getting some resistance from the battery ... not sure how or if the battery would affect it. But, when I had a dead battery once, I had to life it with a drill to load it. Once I unplugged, the drill felt and sounded like much less a load on it and it lifted the camper much quicker.