Okay, some updates!

Firstly Hux is correct, work decided that the coupon is legit, which I am... seriously doubting, but hey, who am I to look a gift horse in the mouth?

Then a couple hours later, the guy who had used the coupon last night came in with a really sheepish look on his face and returned the PS Vita. He said that he'd been "thinking" and he decided that it was a fake coupon and didn't "want the FBI to come knocking"-- his words.

So I returned it and it's all a non-issue now. I can relax~