So you would rather take the lore of the guy who had no hand in Fallout 2, over the lore of the guy who actually had a hand in it, simply becuase you dislike Avellone's views of how the future of the series should go? How petty.snip
Also, according to Fallout 2, Mrs. Bishop got kicked out of Vault City for using jet years before Myron supposedly invested it.
And Myron himself states in Fallout 2 that jet exists because pre-war companies developed a protein extract they had intended for humans, but fed to cows after they discovered any amount of bacterial infection caused it to become an amphetamine.
Humans have been huffing shit to get high since ancient times, and with how terribly scummy pre-war companies were, and given the fact even the fumes of cow shit are enough for someone to get high, the likelihood none of them discovered, or tried to exploit, this new drug is basically zero. Pre-war jet would also explain why Mrs. Bishop could get kicked out of Vault City for using it, despite the fact Myron supposedly hadn't invented it yet.