To clarify, I don’t think the writers did anything wrong. The headline will be misleading because Nintendo’s being somewhat misleading.

I don’t know how much the headline could be improved, if at all.

Nintendo says NS2 GC controller will only “officially” support GC games

Or if they can’t quote “officially”, they could quote “only”. Which could arguably be more clickbaity, but also clue in a casual reader that there’s more to what Nintendo officially says.