I don't care what the party wanted. That's the point. Nobody votes their conscience in gov't anymore. Regardless of what the party wanted him to do, it was the wrong thing to do. Somebody has got to start being an individual. No, I don't think he sold the party out, I think he sold himself out. This tribalism is so deep and so pervasive and now without the McCain example, it'll only fester. As far as the Daines/Murkowski thing, again, it's party over individualism. If Daines was a yes he should have made it his (and our) business to be there to vote. Same with Murkowski. If she was a no she should have voted that way. These assholes aren't being paid to go to weddings and they're not elected to neglect their duty.
Look at the timeline.
Feinstein gets the letter in July, then in the final days possible the letter that Ford wanted secret was leaked (Feinstein accused Ford), that forced the issue into a media circus that was to delay the vote until after the election in the hopes of delaying until trump is out of office.