So - any speculation on exactly what they have on him?
That's the nature of blackmail - "we'll tell your secrets."
Now sometimes they're open secrets like the ones used against a certain unnamed Chief Justice, but one would suppose that normally they would be secret secrets... which leaves us to fill in the blanks based on the information we have, particularly his drinking habit and his orangeness. Both are easily seen even from way out here...
OTOH maybe they just own him. $$
It will all be revealed someday.