In this case, it's unlikely that jumping rope will cause any severe detriment, for the reasons you have already stated. When jumping rope, your kneecap remains in its groove, as knee-bend during the exercise is slight, if you even have any at all. That being said, there is still a chance that your kneecap could slip as the tendons and ligaments are already weakened. However, while jumping rope is good at working your heart and lungs from a cardiovascular standpoint, in terms of the neuromuscular development necessary for your sport it is going to come up short as it is really targets the lower leg (calves) with the upper legs and back acting more as stabilizers for the movement. Remember that like resistance training, aerobic training also has a measure of specificity, and if you are looking for a better exercise to promote the leg and heart adaptation at a low impact, throwing in pool training, either swimming or (even better) jogging laps in a pool will be more beneficial. Water jogging may be especially beneficial as it taps into cardio, strength, and power aspects of training.
In any event with the jumping rope, your best bet is to just remain aware of how your knee feels throughout exercise.
You should also consider your overall leg strength and muscle balance. You are involved in track and field, so you are probably in good shape, but muscle balance may still be an issue. Patella shift is more common in individuals who have an imbalance in the quads, between their vastus medialis (inner thigh) and the vastus lateralis (outer thigh). If the patellar slip is lateral, it's more likely the vastus medialis being under-developed in comparison to the lateralis, and vice versa if the slip is medial. You may be favoring the outer or inner portions of your quadriceps during squats, leg raises, etc. You should have someone (physical therapist, certified personal trainer, or a certified conditioning coach) analyze your posture, gait, and resistance training form in order to determine if any changes need to be made, as well as add additional stretching to your inner or outer thigh depending on which part is stronger.
It's also possible that you just developed a poor patella groove and you kneecap has never tracked correctly. In this and any event, strengthening and stretching your quads and hamstrings, with an emphasis on muscle balance should aid you in maintaining correct patellar tracking.