President Trump should order them to go, then he should go sit in on the hearing and order them to answer.
This is a closed door hearing with all having security clearance.
If either refuses, The President should fire them on the spot for insubordination.
.....”President Trump should order them to go, then he should go sit in on the hearing and order them to answer”.....should fire them on the spot for insubordination.”....
No can do.