We don’t have a lick of proof that he was with Oswald. People of that era dressed in the clothes of the time. Further, there is just as much chance he was sent to monitor Oswald, as any other explanation. There is a mention of R. Cruz having CIA ties. No further data follows, but it is interesting.
I said “whoever the person is.” I, of course, have no clue. I will let the experts handle that one.
Cruz Sr was connected to CIA through an oil&gas firm called Schlumberger.