I'd say it's a scam because they are profiting almost $200 from a simple clerical error that somehow never raised any "red flags" until I got there,
even after a 3 day wait where I got the e-visa approved without qualification before traveling, and their insistence on "cash only" with no paper trail just adds more weight to this notion.
Feel free to disagree, but most people are agreeing this is an exorbitant fee to pay on the spot.