She might be waiting to see if the courts rule in favor of forcing MCGHANN to testify. That hearing is Jan. 3rd. If he is forced to testify, all of them will be, and the hope is some “new evidence” will force more articles of impeachment.
And if the new evidence (McGhan testimony and grand jury testimony from the Mueller investigation) is gained the details, at a minimum, will be leaked to the Democratic candidate(s) to be used in the election.
Seems like this would have to go through SCOTUS ...