You're assuming that the owner is willing to pay that amount when he's made it clear that he is hesitant to do so. Let's also not forget that they could trade him at any point during the season to reduce their luxury tax bill as well as teams have done that on more than one occasion.
Every owner has a maximum luxury tax amount that they're willing to pay and don't believe anything that they say otherwise.
I'm not assuming anything. It's the current situation. You are the one speaking in hypotheticals. The owners have never set a specific number.