The House needs to open a jail at the Capitol again so it can actually enforce findings go contempt.
There is precedent for moving them offsite, but under the building again is better IMO. Keep them under the thumb.
No need for that. Just have a fully fueled jet on standby to fly the uncooperative witnesses to Club Gitmo for a few days of sun and fun with their friends.
While there they can partake in prayers 5 times a day, eat a balanced Halal diet while waiting for their chance to be baptized...