If the investigation is five years old, then this isn't as big of a story as it seems on first glance. Not yet, at least.
"DOJ officials have discussed possible plea deals with Binance's attorneys" is new info, to my knowledge.
[edit] If I were CZ a 5 year long investigation would make me far more worried, not less. The authorities don't investigate nothing for 5 years, after all. If this was a witch hunt it sounds like they found a coven.
Especially with dealing with a bunch of weird international jurisdictions to gather evidence, 5 years is not a long time.
Because it often has to wind it's way through cooperation agreements, other legal systems, etc.