Some things on the auction house make me suspicious...
Two VH feind blast bombs, exact same price, time, and bid.
Two high CTR blast bombs, exact same price, time, and bid.
Unless someone waited for competition before selling their blast bomb, it's logical to assume that most of these were posted by the same person. What are the odds of someone getting two of those at once though?
No.
And they probably just have Darkfang luck.