SH
Why will we “never know” why Saad left?? ( I assume he is still with us and not a victim of the current plague). Yes he will have signed a non-disclosure agreement - but with an entity that no longer exists! so he could speak out now if he was asked, or chooses to do so - although to what effect I know not.
His sudden departure sure puzzled me at the time but I retired a few months later (on schedule) so had other priorities.