Technically, while the agent was slow, you don't have a deal until it tickets.

You might have been able to escalate to a supv on that call to see if they could force you into that fare bucket. You can try again now, but without the agent to explain what happened, it might be difficult. Though the quoted fare may be in the history.

You'd be at the mercy of CO's goodwill, though, because technically, it was not sold in, so it wasn't yours.

A good agent would have confirmed it in before killing the original one. That said, in other circumstances, having an agent like this can work to your advantage.