That's right. And as I've said earlier, take a look at these two scenarios:
Atletico force us to activate the clause and we give Costa 48m. After taxes Atletico receives 32m.
We give Atletico a 34m bid. No taxes, they receive 34m.
In these scenarios, Atletico has no reason to not accept the 34m bid, by forcing us to activate the clause, they'd just lose 2m.