The truth is there's no Constitutional mandate for anyone to certify the election.
He had the authority to do nothing.If Pence had refused to do his job,
It is not mandated/ his job to rubberstamp contested elections. You can't be that dense.
This is the description of the VP's job:
The President of the Senate [the Vice President of the United States] shall, in the presence of the Senate and House of Representatives, open all the certificates and the votes shall then be counted.
And that's it. He's there to oversee the counting of electoral votes -- nothing more.