In all seriousness, If I'm a civil servant (Note not an politically appointed one, just a white collar worker) and the Speaker of the House starts grandstanding about people going to jail, I'm certainly not offering my neck out. If I'm in her position I tell them to go pound sand too. She literally has nothing to gain by testifying even presuming she is innocent and honest people can get tripped up in testimony very easy. If they wanted her testimony that bad they could have easily had it by giving her immunity.
Brings to mind the the quote "If you give me six lines written by the hand of the most honest of men, I will find something in them which will hang him."