You sound very hesitant about a 5th wheel and it seems like you love the hybrid so it seems you answered your own question. :) I really don't think you'd like the sleeping arrangements for 2+ teens in a 5th wheel unless you gave them the bedroom and you take the couch!
I think you'd love a toy hauler if you keep looking and find one in your price range. It would be an ideal 2nd bedroom for the girls. However, you'd have to get a truck to pull it.
Rentals are too expensive and you'd have to get a long one which ups the price.
Have you considered renting a cabin a couple times a year instead? Get one on a lake where the girls could swim, canoe, kayak, etc. and they'd have a ball. Good luck!!
