Any ideas on a clean up crew/ scavenger (group or individual) for going in with a jaguar cichlid?

To give you a better awnser some basic info is needed. What size tank is it? How big is your Jag? Is it a male?

Assuming that you have a fairly large tank, large catfish (over 8", maybe over 6") should be great for cleaning up.

If you have a small tank however, any other fish added will be killed.

IMO, malaysian trumpet snails will be your best bet if you don't have a large tank, and even if you do have a large tank, MTS will be great help to any scavengers you add to the tank :)