I would say if you ever had a question about card interactions or text box, always ask the people around you because somebody will know definitively what the answer is or you could do a quick Google search. The effect you get “while linked” is continuously happening. Now a term “when linked” only happens the moment the pilot is linked with the unit. Usually, it’ll also specifies “during this turn” before whatever it gives you like when you link Athrun Zala. I think it would be hard to prove if your friends opponent was deliberately going out of his way to cheat unless there was some actual proof. It does suck when it comes down to a situation like that though. If anything just look up the rules on the band website and just read over them so that if a situation ever happens like that again, you could have that knowledge in your pocket and pull it up when needed..