@Mason75 Please understand that the host may be more than happy to have a responsible group of under-25s, BUT his licensing and insurance may be in jeopardy if he goes forward with your booking.
1. My licensing defines a guest initiating a booking as being over the age of 25. I will lose my license if I knowingly rent to underage persons.
2. If there is a problem during the reservation, and there is no adult person over the age of 25 in residence or the person who initiated the rental is not present (your mom), my insurance will not protect me or the guests and will be cancelled.
It isn't that you and your friends are not trustworthy or responsible persons.