Is there any explanation for why the special counsel never attempted to interview Assange on the Wikileaks DNC email leak? The whole premise of their investiga

Is there any explanation for why the special counsel never attempted to interview Assange on the Wikileaks DNC email leak? The whole premise of their investigation started with the narrative that Russia hacked the DNC and released the emails through Wikileaks to help Trump win. Why never ask Assange where he got the emails? He’s been adamant publicly that it wasn’t Russia. Why not ask him then who in an investigation that took 2 years? This has always bothered me and intrigued me about Assange.