1. He bought the games sealed at least 15 years before vga grading was the first nail in the retro collecting coffin. Additionally, we don't know that he was buying these games to create an artificial scarcity of supply like the other guy was. I personally don't think that was his intention and my proof is all the other non-rare games he also bought cases of.
2. How do you know it was dumb luck? Maybe these deals were available to anyone that wanted them in the 90s, it was just that no one cared. It would be like someone buying up all the vhs tapes today for pennies and 20 years later they become the hot collecting item. Maybe he was a visionary? Maybe he was just passionate about something when no one else was?
3. Some people don't like making private sales public knowledge.
I think my conclusions are my than likely closer to the truth than your cons are and any reasonable person would agree. Not saying you are wrong, but I think your conclusions are less likely