This falls in the category of the "anything's possible" argument.
Yes, it's possible that Rob blew 40K a year for years while spending the majority of his time away from his family on business and then devoting most of his USA time to video poker. Then it's possible he developed a winning system somehow in a relatively short period of time due to some epiphanies or math insights that nobody else has had. Then it's possible that he decided that time with his neglected family was so important that he didn't want to work OT, but rather took the risk vp might change or casinos would get wise and valued family time above that, so he limited himself to making 100K a year for three years while getting back to even, then continued to win (but at 100K a year) thereafter until he had just enough money for two RVs and a comfortable life with his pensions. And then he retired.
It's also possible he wrote eight years of columns for Gaming Today without referencing number of hands played, where, number of four-of-a-kinds and royals and so on, and continued that for 5000 posts here, and lots of posts elsewhere. It's possible he was training some hundred or more vp ninjas all this time, who as a group have stayed silent due to their jedi training and devotion. It's possible he is willing to train people in this system for free while not detailing the system in any clear, cogent way publicly because he has to make judgements while playing that nobody else can make regarding hot and cold machines and other tricky things.
Coach belly is absolutely correct. All of this is possible. Just like it is possible to play Powerball and win it three times. Or play three million hands of negative EV video poker and be ahead lifetime.
It is on the readers' shoulders to evaluate just how likely it is.