I believe the reason "Top Gear" was 'banned' from filming in the USA was because they had visa's, work and filming permits which allowed them to film for 'documentary purposes'. The American authorities subsequently deemed that the show was not a documentary - but entertainment - and that the visas and permits had been incorrectly/disingenuously obtained.
I assume that their problems have now been resolved and, in any case, there is now an American version of "Top Gear" which must give them some sort of exchange programme!