Guy has got some freakin nerve.. so he must have emailed you from his yahoo account cause I banned his username and ip address.
Just for fun I did a search of his email address on google and found his listing in a few other places none of which you could call reputable job listing services. At any rate if it walks ,talks and quacks like a duck it probably is a scam especially when they have to tell you it's not a scam or even mention MLM (Multi level marketing = pyramid scheme). If nothing else this guy is probably collecting email addresses to send spam to... good riddance