And again, none of them have the sharingan aside from Kakashi so explaining the ‘MS requirement +Uchiha DNA to defeat Tsukuyoumi’ is irrelevant. It’s not a contradiction, it’s simply a basic explanation that says exactly what it needs to pertaining to the party members involved.
A similar scenario would be Black Zetsu stating that Sasuke’s Rinnegan prevented him from succumbing to IT. If Sasuke didn’t have the Rinnegan then that wouldn’t need to be stated.
It doesn't make a difference who he said it to because of the content of what he said. It's not similar to the scenario with Sasuke's Rinnegan at all. Chiyo's and Kakashi's statements are similar to this:
Chiyo: "You don't have to worry about his super knife, because we have super armor."
Kakashi: "
No armor can stop this knife from penetrating."
Kakashi had no reason to make a sweeping statement similar to that, he could simply stated " his ocular genjutsu has you in an instant, none of those methods will work."
Kakashi wording implies it doesn't matter even if they could defeat Tsukuyomi, without time dilation, because when he
can use time dilation