I think $500,000 of his own money donated to the effort is pretty good action.
I dont think another Senate committee would do any good at this point and would just waste time and distract. This is particularly the case since the Senate committees have gotten virtually no support from the DOJ, the FBI, etc. in getting the documents and information they need.
Also, they cant change anything now, but exist mainly as review mechanisms, Once this is over and the rightful winner, Trump, is in place, I think youll see some committee work. Assuming we keep the Senate, that is; right now thats the crucial thing.
It was left over campaign money that he begged from Trump supporters.