It looks like Rey Mysterio's son Dominick is indeed being lined up for some kind of angle with Seth Rollins... although things didn't play out quite the way it was rumored they would.
Last night's "Retirement Segment" really didn't come to much (Aleister Black defeated Rollins, paid the price with a Stomp), and Mysterio wasn't actually involved. The legendary luchador actually appeared in a different segment later on to address The Monday Night Messiah's "tribute," and reveal that he wasn't sure if he was going to be cleared to return to in-ring action.
Dominick then joined his father, vowing to get revenge on the man who almost blinded him by sending a very clear message: "an eye for an eye."
Dominick could still wind up betraying his father and becoming one of Rollins' disciples (WWE is not exactly known for its continuity), but it seems far more likely that this will lead to a match between the two at some point.