I don't know what Guiliani has in mind, but it is certain that this SC investigation was illegal from the start because the Special Counsel statute specifies investigating crimes, NOT counterintelligence whirleygigs.
Mueller could not investigate the crime of collusion because collusion is not a crime, and conspiracy would have been monumentally difficult to investigate, let alone prove.
No, the purpose of the Mueller investigation sham was to hang a dark cloud over the Trump presidency and to block investigations of the investigators... and they kept this stage play going for two years and created an issue for the 2018 Congressional elections.
the Special Counsel statute specifies investigating crimes, NOT counterintelligence whirleygigs.