We had a pilot in my old squadron who was medically retired for some sort of "psychotic episode." Completely awesome guy, great pilot, no history of anything until one random day he got some insanely bad headaches and migraine type symptoms. Next thing you know, they give him an anti-psychotic drug that permanently DNIF'd him. He's doing fine now, but no longer flying. And it appears that his one-time episode may have been a reaction to one of our immunizations.
Hopefully everything turns out OK with the AC incident. Just like anything else in the aviation industry, rule #1 is to sit back and gather facts before jumping to conclusions.