Those 4 people are not fit to run any company.
Not a single person asked: well hey what if somebody asks for an evidence of lying? Do we have one?
Even the email to their own employees says it is a irreconcilable difference. Nothing about lying.
I don't think it is reasonable to go with "we don't know". It is more like: "it is crucial to back up your claim. Still, you don't.".
You don't just accuse someone of committing a heinous crime and stay silent. What is the detail?
You think accusing someone of lying in a public statement and don't follow up is competent?