This is affiliate marketing and you can really earn as much as you want base on the product you're selling. And on this case, it's the commission that you will get every sale you make for their coin. It's a popular marketing strategy so if others are looking to it as something hard, well actually, commissioned basis profit is difficult from the beginning that's why if there are job offers and this is the compensation they offer, many are declining it. The title may be disappointing for others and that's why you should probably add the term "as much as" on your title.
yes I am also curious why he would share if he could do it himself.
the main goal might be to look for a ref, but maybe there are other intentions, I'm not thinking badly, but people who are too good are suspect.