Only one required a senate investigation.
That doesn't answer the question. And the Senate investigation wasn't required, it was undertaken for political and civil purposes.
You used the term "Big Lie" but that's a framing opinion handed to you by the media. The media wants you to believe one thing is a big lie while ignoring the other big lie.
No state is going to investigate itself and conclude it engaged in fraud and corruption. Just not gonna happen. The last thing elected officials can afford is for citizens to lose faith in the elections. Hence, the report's conclusion of,
"Our clear finding is that citizens should be confident the results represent the true results of the ballots cast by the people of Michigan." That was a foregone conclusion from the beginning.
The report concluded there was no "no evidence of widespread or systematic fraud," but made no mention of narrowly targeted fraud, which is the most common type of election fraud that can influence an election. That's why so many people have a death-grip on "widespread."
And despite the conclusion of "no evidence of widespread or systematic fraud," the report has a laundry list of significant issues and problems that must be addressed (which would be unnecessary in the absence of fraud or "move along, nothing to see here").
The report concluded that no dead people voted. Except in the cases where dead people filled out absentee ballots and sent them in and due to "clerical and timing issues" got counted.
The report also concluded that no one who had moved out of state voted. They did find that people who had moved out of state who received unsolicited absentee ballot applications, filled the applications out, and then received an absentee ballot, they voted. But that was probably insignificant hardly enough to worry about.
The report found partisan poll worker recruitment in Detroit and Wayne County, where there were virtually no Republican poll workers (or observers) after Republican volunteers were either ignored and not called back, or they were told there were already enough workers. The report concluded that is a serious issue that needs to be addressed. Even though it's a significant irregularity, it isn't fraud and isn't widespread relative to the entire state. It was pretty widespread throughout Wayne County, though. <snort>
The election is what it is. None of these investigations or audits is likely to find anything of significance that would go to undermining voter confidence in elections. The only things to come from these investigations are the problematic issues that need to be addressed to reduce the incidents and opportunities for cheating and fraud.