I disagree completely. And I don't hold them (WL/Assange and The Guardian) equally credibility wise.This isn't a trial and the equivalence is just not there.
The Guardian are a respectable source of investigative journalism and Wikileaks is literally a vehicle for Assange and his agenda. When one of these sides makes a claim that the other denies, only a fool would put equal weight to both sides.
You can say this is not a trial but a trial is honestly the only context this has relevancy in. The goal is to prosecute the Trump campaign. You have to have a perfect case with tangible evidence and even then you have to convince a grand jury to convict.
This is informative to a largely clueless community like us but to Mueller this is nothing and likely something he already knew.