Americans are prudish, but not such that he would lose his job over an affair. A few Americans would boycott his company - but not enough to matter. There will be general disapproval, but that is as far as it will go.
However he will lose is job over an affair with someone that he has any form of business relationship with. He can have an affair with a nurse in the local hospital of the waitress of a local cafe and we will ignore it. However the girls he had an affair with are off-limits, and should be for any culture for reasons that we think should be obvious.
Isn't there a thing that when it's consensual, tell HR and done? Or you have to be on the level at the org? It is not a law, but in my previous not big, but ~ 1K international org, many marriages and many babies.
Did he do anything besides infidelity, as it seems that the "board" knew about that anyway.
In any case, he fell on his sword, and I wish him well in the afterlife, nothing is black and white.
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