Well, just ban him from leaking information, and that's it.
It's better to leave immunities only for GMs and those eliminated in the first night. If someone missed a few games, it's their own fault.
I also think it would be better to remove immunities altogether.
Ничто не возникает из ничего и ничто не пропадает бесследно.
Если где-то чего-то убудет, то в другом месте добавится.
(Закон сохранения).