Yes, with your clarification that the second camera behaves normally, and that the problem camera has power and stabilizes, the slip ring wires become a very high probability. Even if the camera is dead, the slip ring is often the problem.
1.) Pay particular attention to the White wire and the Green wire. BOTH have to be normal for EITHER pan or tilt to work.
2.) These are the most common slip ring problems I have seen myself or heard others discuss:
a.) A break in the wire, especially common at the metal edge of the slip ring casing.
b.) A short at the edge of the slip ring housing. (insulation gets cut by the edge of the slip ring casing)
c.) Wire broken at the solder joint of the contact plate
d.) Damaged wire insulation caused by using the short rubber dampers. (I have seen others report this.)
3.) You may have to unplug the lower connector and check for continuity. The failure occurring intermittently, especially after a calibration (lots of movement in a short time), suggests there may be a problem with the brushes inside the slip ring.
This drawing shows what each wire does (to the best of my knowledge). I thought it might help as you look at the wiring:
View attachment 18222