However long he worked there, he didn't bite the hand that was feeding him, but when the party was over he did turn around to bite the hand that fed him.
Being moral about the NDA does not weigh up against working there in the first place, and I don't know what $16 K means to a high profile Dubai consultant, it may have been substantially less than the severance pay he was entitled to anyway.
I don't think anyone was claiming that being moral about the NDA does "weigh up" against working there in the first place. If he were trying to paint a glowing picture of his own morals, he wouldn't have written the article in the first place.
(Since he appears to have been there for something like 6 months before getting fired, I'll hazard a guess that his severance pay wasn't all that spectacular.)
10 K+ per month is not unusual, and depending on his contract they may have to 'buy you out' (for instance, after three months they might have signed a years contract with you including the first three months).
So the severance could be anywhere from $5K up to a very substantial amount of money. The fact that they're willing to pay another $16K just for signing an NDA suggests it was a pretty high salary.
He already said, kinda, what the salary was: with bonuses and whatnot, he expected to be getting $200k per year.
Given what he's possibly done to their reputation (I don't know; perhaps everyone already thought they were corrupt and dishonest anyway) that he wouldn't have been able to do if he'd signed the NDA, I don't see that an explanation in terms of salary is required: getting everyone to sign the NDA greatly reduces their exposure to this kind of bad publicity.
Being moral about the NDA does not weigh up against working there in the first place, and I don't know what $16 K means to a high profile Dubai consultant, it may have been substantially less than the severance pay he was entitled to anyway.