You are incorrect.

That being said, it is dependent on two things.

Some jurisdictions may only allow for a single contract. I don't know where you live, but in my part of the world there's nothing stopping you from negotiating a personal deal. But it can't undercut the union minimum.

The second is the more important part - does the company want to negotiate with an individual? Most places don't. It costs time, money, and effort to do salary negotiations. Companies don't want to set individual contracts for 500 different workers.