It may well be the case that this Farrell guy isn't legit, though. I highly doubt that actual high profile fight-fixers would willingly expose themselves due to potential trouble with law enforcement and retaliation from the underworld who lost money on bets, but they are certainly out there.
If it is about all book that he is promoting and to make money out of it, it's not even worth it, he will be in trouble all his life, from the authorities from organizations and from the syndicate, he is limiting himself for this and he will be targeted for liquidation at worse, there are many rumors about mafia involvement but no one's coming out to expose this, until this one, hope he has all the means to protect himself.