Sounds like Bonham's should be held accountable and return the money. But I did read the auction listing and it clearly says the car is under customs by the UAE and money is owed on it. That alone sounds very sketchy.
PANTERA INTERNATIONAL
A DE TOMASO CAR CLUB
Presents the De Tomaso Forums
The On-Line Meeting Place for De Tomaso Owners and Enthusiasts From Around the World
Clicking on the banner will take you to the sponsor's website.