That they'd never heard of the key? (I hadn't, as the slate reporter seemed to anticipate with their "might be a little hard to follow" comment)
> http://www.slate.com/blogs/the_slatest/2016/08/09/wikileaks_...
Offering a reward is not the same as "[posting] wild conspiracy theories," which is what you claimed they did. Posting a wild conspiracy theory in this case would be openly accusing a specific person or group of people of murder with no evidence.
I would call this "wanting to fact check a conspiracy theory," which I view as a good thing generally, and especially good in the case of wikileaks.
> Intentionally misleading/lying isn't being incompetent. They could know or think that it was an accident, but intentionally spin it as foul play to reinforce the narrative they've been spinning.
They could, but this would require them to assume no one would figure out the actual cause -- aka a lot of cost with no benefit. Seems surprisingly stupid/pointless/shortsighted.