This kind of thing isn't good for the party as a whole. Hillary doesn't need another scandal and we don't need her to have one. Yes, firing three people would be enough to satisfy me she handled the problem. Then a quiet investigation to see the extent of the problem.
Clinton and the DNC to be investigated. Nothing at this point shows them to be honest in this situation.
That is my point. The Sanders campaign conspired to steal from Clinton. They want the DNC and Clinton to be investigated for it. They are a one trick pony. Under your scenario they would ask for the same thing. It is the lowest of lows in campaigning.
I know this. If Hillary had stolen data from Bernie, his supporters would be asking for a Congressional investigation.