I never cease to be astonished at the imagination and variety of fantastical excuses people manage to invent for aircraft accidents.
For highly experienced professional pilots this seems very hard to explain without pilot incapacitation or mechanical failure.
Highly experienced Professional pilots seldom concur with double jeopardy 'theories'. In the sim double jeopardy situatons are nowadays (thankfully) almost exclusively banned. In 99.8% of cases if it looks like a duck, flies like a duck and quacks like a duck it almost certainly isn't an almost extinct lesser spotted golden eared fantasybird.
No pun intended, but the report on this will without doubt indicate this tragic suituation was a complete 'turkey'.
Virtually no-one pulling a tight turn to follow in a tailchase looks below and to the side of themselves - even if they could in an aeroplane with as renowned poor visibility as the P63 - he'd have been fixated on up, ahead and left. The B17 was probably obscured beneath the engine cowling and under his right ear. And no criticism intended, if as reported he was an Airline pilot did he really have the instinctive continuously scanning rubber-neck lookout of a fighter pilot? As an ex mil pilot gone airlines I found to my chagrin that bollockings ensued at the gliding club due to my almost total loss of basic active lookout...
None, all or some of these thoughts may be relevant.
Texas Raiders has a place in my heart. She was the first aeroplane I ever turned a spanner on. Changing some hydraulic pipes as a volunteer at Harlingen in 1977 which kickstarted my entire career. I wonder if they were still there...