Quality Market Research Tried to get me to cash a cashier's check to check quality for Western Union New York, New York

Received a Cashier's Check in the mail today for $3,700 from Quality Market Research to do mystery Shopper and when I tried checking them with BBB like they said that they were listed with I couldn't find anything out about them.  So than tried just finding them with goggle their company name and got no where their either.  So than went to their name with scam at the end and found another report but the name has changed.  But everything else was the same down to the stores that they wanted me to mystery shop at.  They are Sear's, Wal Mart, Home Depot, ect.

There were a couple red flags in the letter to that caught my eye when I sat down to really look and read this letter.  In the address no space between west and 44 and west was not capitalized.  Also the name of their company is spelled wrong in the body of the letter.  For sure I will be filing a report with the authorities as soon as I can to try to get these scumbags out of business.