There was, they just chose not to use an anti-democratic loophole to do it. They took the high road by not using a recess appointment. Sure, that appointment would have only been temporary but it would have allowed some votes to get passed the 4/4 split at the time. It also would have been less of a campaign talking point for Trump to be able to appoint someone immediately (the temporary appointment would have been until 2018 I think??).
I don’t know if they could have filibustered the vote on Trump’s final pick during the election year. I’m not completely caught up on those rules.