Thank you. This is more than enough reason to leave negative trust.
This makes me very happy that you tagged these guys. I haven't seen many of the obvious merit buyers & sellers getting any consequences, and I got the impression that DT members were backing off of doing so. Not tagging them IMO gives them the confidence to keep doing it, and they will.It does not make me that much surprise. I have seen people are exchanging merits shamelessly yet they claim they are not abusing it.
Well you know, scammers and other dishonest people are known to deny it when you catch them performing their dishonest acts. 
This case has been on the radar for some time. I reported the case
It's still good you reported it and again, I'm very glad tagged these users.