I'd be surprised that anyone would fall for this. That's how obvious it is. Self moderated and locked thread is never legit.
But honestly, the digital goods section is flooded with scams like this. It doesn't matter what payment processor or payment method that they are conducting their trades via, if the rates seem too good to be true, then they are, 100%. I see this a lot with absurd discounts on paypal balances, and gift cards that are sold in the same subforum. People can spot this WU scam from a mile away, yet they seem to think that gift card trades are different or something. Just don't be greedy and avoid them, because even if you do get paid (very unlikely), chances are you have received fraudulently obtained funds/gift cards.
BTW, could davidx2019 be an alt of DavidXXXX which is a known scammer with a ton of alts? This is completely unbased, and pure speculation. But there is a possibility given the similarity in the names.