Hmm.........does he really say that? I'm surprised. Only read the first few paragraphs, then scanned the rest, so didn't pick up on that. No, I don't believe the lake of fire judgment is past. That's Satan's future fate, along with Death, etc. I'd better check a bit more closely in future before posting any more links. So yes, Satan is still very busy, and he (or one of his emissaries) can certainly take up residence in willing 'victims' today.
And as you say, this is not a contradiction of the idea that he is presently bound. That's one of the points I'll be covering in one of my more substantial posts in the near future. I'd better stop calliing 'em 'humdingers', coz that joke is now waring a bit thin, & sounds too much like a boast. I think 'article' will suffice for now.