The stupidity of this is beyond words. To just join any steam group that you get sent invites to is like being given a bag by a stranger who tells you to hold on and not look inside. Then when the cops find it and you say, "Officer that bag isn't mine some random guy gave it to me I swear." You are an adult and responsible for your actions. Ignorance is not an excuse.
People might look the other way if this was the first time something like that happened but it is the third time in two months some weird stuff has come out. First it was the porn history and the glorious cope of, "I was hacked" and "I have not looked at real porn in two years". Then the Tux stuff comes out. And now there is all this weird stuff with a small German steam group and a profile of a pedophile.
Flamanco is the ultimate patsy and will probably glow in the dark at some point. is incapable of taking any responsibility for his action hoping that ignorance as a defense will work. This is your brain on anime and vtubers. Pretend to be a ignorant child long enough and look at that he became one. Just give up and do a room tour. Your place probably looks similar to this.