It appears the Dems used Flake as a tool to achieve its desire for a delaying FBI supplemental investigation, but it probably backfired on them.
Re the quorum and vote: IMO Grassley didn't need either in order to advance the ball and any business that was transacted could have been ignored by the senate.
However, both McConnell and Trump immediately agreed to Flake's stipulation as an effective means they could control of resolving any lingering doubts the R fence-sitters may have.
Grassley could have sent it to the floor without a vote or even a negative vote but there is no reason to fear hearing from the FBI again.
Are they going to say all our prior investigations were BS? I don’t think so.
Besides this is NOT hurting the GOP but the Demons. They are showing the entire nation their asses, in technicolor.