WASHINGTON — The fate of President-elect Donald Trump’s Cabinet is still unclear after Republican senators spent much of December carefully dodging questions about Robert F. Kennedy Jr. ’s views on vaccines, accusations of sexual misconduct against Pete Hegseth and Tulsi Gabbard’s 2017 meeting with then-President Bashar Assad of Syria. While some GOP senators have indicated they are all-in for Trump’s picks, others have withheld support, for now, especially on some of his more controversial nominees.