I'm sure he would have tried, but we're dealing with massive hypotheticals at this point. Under your argument, we should not have a justice at any point ever step down because McConnell would try to block a nomination. Yes, he would try. Doesn't change the fact that the best move was for her to step down at the beginning of the term.
We should honestly be pushing for justices getting on in years and having health issues to step down at the beginning of presidential terms regardless.