We don't need to speculate - the article discusses his legal options. He explicitly chose not to pursue it for what he claims was the cost.

There is no multi-million dollar award - this isn't a TV Show or something.

Arbitration would determine, after examining all facts presented by both parties, if his account should be re-instated. Further, if his account is ordered to be re-instated, he would be awarded "reasonable attorney's fees", which would cover the cost of any legal representation he hired to argue his case.

So yes, he needed to pursue the legal path here, but chose not to. The quoted dollar amount in the article is peanuts, and like previously stated over and over, if he's so certain of his innocence and has all this supporting evidence, arbitration would ultimately cost nothing. ie. there's no reason to not pursue the legal path here.