Lancelot it is almost certain that a Blue Steel was fitted to a Victor 1. Probbably as a trial as no Mk 2s might have been available.
Torkadoken, I see where the confusion may arise over the Gnat/Vulcan fit. Brookes in his History of the Airborne Deterrent at page 131 has the diagram stating fighter-support for the Vulcan. According to the Avro proposal they were supposed to land in friendly territory or return to mother for refuelling from a specially installed flight-refuelling drogue.
Apart from the need to modify all the Gnats as fighters and AAR capability it would have been essential to provide the Vulcan with its own AAR to top it up.