Leaving aside whether others would believe Lis's words, what good would it do even if they believed?
You must know that Demon Prince Demogorgon has been scheming for many years, and it is not something Lis can change.
Just as the flapping of a butterfly's wings can eventually cause a storm, it ultimately cannot change the already formed terrifying hurricane.
Even if Lis were to make public everything Demogorgon had planned, at best it would just expedite Demogorgon's scheme, without affecting the overall situation.
But in that case, Lis's existence would undoubtedly enter the sight of Demogorgon and All Gods.
With his current strength, he would simply be courting death.
Not to mention Demogorgon, even among the camp of the gods there are deities with dark and evil intentions, so Lis must be careful.
Although up until now, he has been very confident about everything that happened, Cecil cannot.