It's been fairly obvious to most game developers for years that in-game communications are a relatively secure system for communications, simply because they have a sort of code built into them. And since terrorists and other bad actors have been known to use online games as a communications platform, it should not be surprising that the Deep State has too.
If Q is correct, one game being used for that purpose was Star Wars: Commander. Certainly some of the in-game exchanges there appear to be unrelated to the game nominally being played. So, it may be significant to note that it is being shut down as of June.
GAME CLOSURE ANNOUNCEMENT
We have come to the decision to shut down Star Wars™: Commander on June 12, 2020. As of March 13, 2020, all in-game purchases have been suspended. Star Wars: Commander will remain playable until 11am GMT on June 12, 2020.
I would expect that there is also a considerable amount of money-laundering taking place in the case of some of the more inexplicably successful online games.