Yes, fines to be paid for personally by the issuing senator. That would stop this nonsense.
No, that should be prohibited. The senator who authorized the admittance of the people who disrupted the hearings effectively enabled the behavior of those protesters thereby wasting the committee’s time and taxpayer money.
Therefore, the senator should bear the cost of the disruption (by paying a fine), not the taxpayers who were “harmed” by those who interfered with the lawful conduct of said proceedings.