Please correct me if I'm wrong, but all I think we know is that he TESTED positive for COVID, presumably via a fairly sensitive PCR test. I don't believe we know if he was symptomatic/ill. There is a strong likelihood that we are all being exposed to the coronavirus in our daily lives. But so many of us have "had it" and are vaccinated, that our bodies are now able to fight it off and prevent illness. However, there is potentially a period of time while the virus is multiplying and the immune system is fighting it, where maybe it takes a little bit longer, and so there is enough viral load at some point to test positive via PCR. And when that happens, you have to take a 10[?]-day timeout, but there's a good chance you have minimal or no symptoms. As far as being contagious to others, I don't think we actually know what the threshold is for that, but we obviously continue to err on the side of caution with the isolation.
So I think there's a lot of nuance about "he had COVID twice" that is getting lost.