He didn't know how much power Kaguya possessed so it’s ah no for me. She would have neg diffed him probably.
Kaguya made an army because of them so she was scated enough to do so. Perhaps(likely) they had a way to extract the fruit/power from her so that's a yeah.
IDK... Momoshiki's abilities are OP. All he'd do is just absorb any ninjutsu making Hagoromo basically useless. Kinshiki will pin down Hamura, their taijutsu user of the team.
I'd say Kaguya will have a chance as she can use god vacuum against Momoshiki.
Momo and Kin would beat Kaguya. Simply because Kaguya is a moron who would give Momo all her ninjutsu. but if Kaguya is logical she could easily win.
That’s why I included her sons.
They perhaps could make up for what she lacks in intelligence.
Momo and Kin stomps.