I banned the two users.
Regarding what you're saying,
You can check their profile etc via ^
The main thing is if you visit the seller's thread, you can click on their IM button in their profile to add them and if you've already added them, it'll open up the chat box for the seller. There's honestly no reason why someone should get scammed by an impersonator if they take 3-5 more seconds to check through a few buttons.