As goofy as it is, I don't think Night Interceptor would grant an extra die in this case...
If there are no enemy Fighters in the same sector as this unit, this unit rolls one extra attack die when making Antiair attacks against enemy Bombers. In Darkness, enemy Fighters must make a successful search check to negate this bonus.
Even though the Beaufighter is straffing, I don't think the "Interceptor" part of Night Interceptor works. Doesn't effect this shot, just something we should both be aware of.
I wish to have no connection with any ship that does not sail fast; for I intend to go in harm's way. - Captain John Paul Jones