I'm just wondering if it would be a good idea to call the owner. There may be a reason that he worked out the deal wiht the FBO, what if he has a signed agreement for the FBO to sell the plane.
If an apology to the FBO does not get the negotiations started again, I would go elsewhere.
Just my opinion. That and a dollar and a half will get you a cup of coffee.
Pat
Never run out of altitude, airspeed, and ideas at the same time.