If your running a large business and your second biggest customer is threatening to walk you give them the best deal possible. You certainly don't tell them like it or lump it. This is the problem with the EU, we are just a cash cow. They respect nobody, they have become to powerful and just think they can treat countries like shit. We need to leave.
A business would hardly be inclined to try and give you a good deal if you tell them you are leaving no matter what they do, that you may not pay money owed, that they have been ripping you off then one of your reps stands up in front of them all and personally insults them. There’s not many businesses that would still say they want you to stay and then give you extended time to go and find business elsewhere.
Most companies would have simply told you to **** off a long time ago.