That WaPo article was put out after a ton of criticism that the US media was refusing to report on it. The original news about the key witness admitting to lying and fabricating was released on 26. júní 2021:

https://stundin.is/grein/13627/

WaPo finally put out that article on July 8, 2021 after criticism of western media.

These search still get zero hits for anything related to this news:

site:cnn.com assange witness lie

site:nbcnews.com assange witness lie

site:nytimes.com assange witness lie

site:apnews.com assange witness lie

site:msnbc.com assange witness lie