Comment by ivraatiems

I guarantee you that if OP said, sorry, do this or I am going home, they would have done what needed to be done. Both in terms of payment, and in terms of getting their software and hardware houses in order.

It might have involved OP getting a taxi to the airport and being chased down at the gate, but it would have worked.

And even if it didn't, they would have saved themselves enormous time, money, and stress by following through on their threats if it didn't work out.