The first meeting here isn't a retcon, it's just exploring something we haven't seen before. But that's been said already. And the whole kiss thing? One kiss doesn't constitute a relationship and they were mindcontrolled at the time anyway. Rogue even said she doesn't want to acknowledge that as their first meeting or kiss because it wasn't fully them. She didn't want their relationship to be tainted by something out of their control, but something wholly theirs.