The manager failed to properly manage a difficult person. Both of them seem to be quite hard to work with.

I would put most of the responsibility on the manager - he is supposed to handle these situations, and get the most of people, including difficult contractors.

But the contractor should have been smarter about the reality of being a contractor. You can’t afford to be this annoying if you don’t have job stability.

Everyone seems to be in the wrong here. Hopefully both sides learned and grew from this.