does the Jan 6th, 2009 proceeding allow for a period of discovery, search for documents?
I don't know, but my guess would be no. They'd probably just have an up or down vote. I imagine a lot would depend on how egregious and shocking the evidence and what the public's reaction to it was.
It would be interesting whether the SCOTUS would allow itself to become involved. They might just decline to take it up, on the theory that it is up to the House to impeach and the Senate to remove.
It happened in 2005. The Donks tried to get Ohio's electoral votes tossed, on the grounds that there had to have been fraud because of the discrepancy between the exit polling and the actual vote. They didn't get far.