How long have you had the RV? If new it could be leftovers from when they cut the hole in the Tank for the drain. If old use the auger (hand crank instead of drill) and go slow. It should not get stuck because you can always reverse the direction and pull it out.
What kind of paper have you been using? Do you flush with plenty of water after using the toilet? Do you wait until it is plenty full before dumping?
Not being noisy but the answers might help someone (possibly you) figure out where the clog is.