Is this the same person, if you look at the @USDEXCHANGER LTD account, doing the same thing as what was done by:@Buyselldollar.
Yes, they all are either a group of person a single person trying to pretend as others. Someone has already mentioned about the btc dude in that thread as you can see.
MAJOR SCAMMER ALERT!!
this guy is btc dude, stay away from him!!
he will scam you till you die, resurrect and die again!
From your investigation, everything seems okay but one thing I can't understand. None of the phone numbers listed are from Bangladesh. These numbers are from other countries. This is more shady too.