My bad, I am sorry mate.
Yes, I'd be joining the excitement, since my team (Sevilla) no longer would face Griezmann, but Gil Marin is firm on the fact that Atletico can't negotiate about anyone, not even the bench players. That is solely because of their transfer ban. But if United are capable of paying the clause, no doubt. If paying less than the clause? The challange is getting through Atletico.
I may be naive, who trust Gil Marin and Atletico for their stand point, but I don't think this is a facade, I actually believe it will be hell negotiating with them, and it is better off to pay the clause. Because selling players would also inderectly make them losing the trust of Simeone, so I think they value their tie with Simeone a lot, since he is their messiah. However, as you implied, crazier things have happened in summer transfers; this summer could be a proof on whether Atletico's board folds or not.