All they'd need to do is leak a single email, or even a snippet of a single email that was in the relevant date range but not released, and assert that WL had suppressed it.
FWIW we also saw HRC and her cronies claiming that the recently released emails were doctored. They made this claim straight-faced and it was cryptographically proven to be completely false.
So claims about WL's motivations and actions have thus far not stood up to scrutiny, and our officials have thus far been proven to be dishonest.
Their motivations are irrelevant. Proving politicians are hypocrites is easier than finding metaphors in the bible. Their releases have undeniably been assimilated by one candidate using WL's credibility and flavor of scandal. WL went along with it.
"Troves" don't have signatures. Omissions and context matter. See the ICIJ approach.
FWIW we also saw HRC and her cronies claiming that the recently released emails were doctored. They made this claim straight-faced and it was cryptographically proven to be completely false.
So claims about WL's motivations and actions have thus far not stood up to scrutiny, and our officials have thus far been proven to be dishonest.