Would that be the same US Federal Marshals that work for the DoJ run by Eric Holder?
I believe the Sergeant at Arms would be responsible for arresting someone for contempt of congress. The charge is wholly contained within the legislative branch, and is not enforceable or modifiable by either the Executive or the Judicial branch.
They are part of DOJ but they won’t hesitate to fulfill an order from Congress on such a charge. If they won’t, I’m sure that there are others that will.