Regarding the victim buried alive, I doubt it's a clue. Because it can easily be interpreted as a description of an action. But if it were "a blonde buried alive," then I would agree that it's a clue.
And maybe we should still include in the plan somehow getting information about whether you, Ment, blocked Shizuo on the first night or not? Think about it, it would be beneficial for you to prove that you are a Town member.