AFK....
Remember....wirbelwinds are prey to most gv's, but when you're AFK, you can't shoot him or run from him. He had a lot of time to do whatever he wanted to that tiger.
I have seen weirder than that..., 3 AFK interpters fly right past my 35k B29s, plus I've killed multiple tanks in my Osti, as well as 3k B29s over TT. Also did a test in a custom arena with this, takes a 3sec burst from 5 feet away from the rear of a tiger. It is possible, just
VERY improbable. Oh, did I mention a formation of B29s main gunned by a few tanks, all of these I find less likely than a tiger going AFK for a few mins without knowing enemy GVs are present.