Did they say they had proof, or that they could prove it? There is a big difference.
What I remember them saying repeatedly was that the publicly reported election results exhibited statistical anomalies - raising huge red flags. That this was probable cause for further investigation.
What I remember them saying was that the very limited access they had to the machines, software and other evidence only reinforced their doubts.
What I remember them saying was IF they were given full access to the machines, software and other forensic evidence, they could prove one way or another.
Why were they blocked from getting that access at every turn?
You remember it correctly. All other BS is just more BS.