Given the safety record of Air France from 2000-2010, I don't feel this is that much of a reach. The last part about AF wanting to see Concorde grounded/Airbus increasing charges to BA etc. may be a bit of a stretch. I mean, if AF wanted to park Concorde they pretty easily could have just done so.

With that said, the rest of the story is certainly believable and I could definitely see AF trying to cover up their own deficiencies by trying to blame a piece of FOD as being the only cause of this accident.