Depending on how aggressive the RD really is, maybe.
In a 75 you could house a hypostumos punctatus, one of the "common" species would be fine. They don't get overly large. My small RD male left it alone in the quarantine tank.
Starting out with them together from the beginning gives you the best odds of having both fish live together. At least that has worked well with current RD and pleco living together now. Cichlids tend to ignore bottom dwelling fish as they get larger, but they tend to dislike new tankmates and can be extremely hard on them.