It is VERY difficult to say whether it is an addiction or not, because it is not clear whether the person wrote this seriously, out of emotion or being balanced. Maybe this is a form of humor or sarcasm
But if he wrote this completely seriously, then I cannot definitely say that he has problems with addiction, but I don’t like it. I mean this person may have problems with attachment to the game
Even if this was just a joke, due to the context in which this happen in which the members of that group have made bets for 2 years in a row, it seems safe to me to speculate that some of them may have some problems, as betting for so long when combined with that kind of message may seem to indicate that they are not planning to stop, and unless a person is very wealthy, betting for that amount of time is bound to get them in trouble.