They will not be able to. It is going to be a private ceremony and none of the details have been released.
Liberty University is also a Private Campus. I know that they have a Campus Police Department. I hope that they would keep them off Campus.
Actually it's on Tuesday, at the church he founded and pastored, with overflow feeds to the school's football stadium and basketball arena. That's a total capacity of somewhere near 40,000 people if they were to fill them all. Not exactly private. The interment will be private though. As another poster mentioned, the campus is privately owned; the protestors will have to stay off campus. Hopefully they'll all be run over by the hearse.