If he has and holds evidence of something so damaging that a tweet of the supposed hash of the file is enough to be a threat to a person in power, then why has he allowed himself to live under effectively self-imposed house-arrest for the past 4 years?
I can't imagine that the Wikileaks apparatus doesn't have sufficient op-sec and op-capability to ensure that whatever they're holding gets released effectively should they choose for it to be, so I find myself erring towards this being an over-played hand for the most part.