Paying people to be controlled opposition is expensive.
My observation is that politicians that play the controlled opposition game prefer to trick people into that position.
I've noticed that pundits on both the left and right play the game of setting up the weakest players on the opposition so that they can control them.
The left wants Alex Jones and Glenn Beck to the the definitive conservatives because it is easy to frame and manipulate these clowns.
The right promote AOC, Fetterman and related clowns as the definitive speakers on the left. It is easy to frame these people in a bad light.
BTW, Your question was
"How you can tell if someone is controlled opposition?"
I believe that a better question is:
"How can I be sure that no-one is trying to set up me as controlled opposition?"
RE: How you can tell if someone is controlled opposition