it occurs to me to ask if you have made sure the rollers are turning, not just smooth. If film has to slide through them, they have to turn or yes, you will get scratches.

if one or both are not turning, i fear it may be time to have the camera serviced -- not because of the rough spot on the roller, but because if there is a rough spot on the roller, and there is something making the rollers not turn, there is other trouble elsewhere that also needs attending.