The way you currently recruit her having sided with her, is already perfect
We will have to agree to disagree. I think siding with her over the grove is both mechanically stupid and so narratively dissonant it basically is a meta-gaming route.
Cool, now read the rest of that sentence. What I meant, quite clearly, is that recruiting her by SAVING HER FROM THE TORTURERS works perfectly whether you side with her or against her in act 1. That meeting her in act 2 having sided with the grove, and rescuing her from the torturers would work perfectly. Quite often complete sentences have a different meaning than individual words within them, it's wild.
Minthara is the best character and she NEEDS to be recruitable if you side with the grove! Also- I support the important thread in the suggestions: Let everyone in the Party Speak