Hi, I tested it out and if you recruit the bandits at least the day before giving her the dress then you can have both Mina and the bandits. (I'm not sure if you have to have Mina as a prisoner first or not though.)
@WolfLynd Thanks for the data- I did some testing as well with it- seems like there are a lot of ways you can sorta be a dick to her and then bring her back into the fold with the dress- including recruiting the bandits as you've said. Min maxing in the game turns out to be very fun- I wonder what else I am missing about the game.