Being actively under indictment is a lot different than just being investigated. Indictment requires that sufficient evidence has been gathered, reviewed, and (for a federal case) at least 12 of 23 jurors in a grand jury believe there is at least a 50% chance that you have actually committed a crime (12/16 jurors at the state level).
By the time you have been indicted you have received a lot of due process resulting in a concrete belief that if you go to court you will be convicted of having committed a crime.
Waiting on “We investigated ourselves and found no wrongdoing”.