I really like the way you recruit her, I agee we need a path to recruit her with a good Act 1 choice ending, I even started a thread about it in suggestions but it was moved so I guess we can't make suggestions about characters? But I'd like it to remain the same act 2 recruitment we have now.

Have her escape near the end of the fight, shaken and having experienced silence during the fight creating the seed of doubt that when combined with her being punished and tortured for your defeating her, allows you to recruit her. The way you currently recruit her having sided with her, is already perfect as a means to recruit her having sided against her.
And if she was available in both act 1 resolutions, they'd have the incentive to finish her character.

I would hope for this to be patched here, not hinged on a single enhanced edition that fixes everything. An update to make her recruitable in both paths, given she already has voiced dialogue for characters she is currently mutually exclusive with, is something a general patch could include, no need for the remaster?

Also wildcard idea here,
If Larian wasn't so anti-DLC I'd even suggesting adding her as a DLC origin character, where you'd have a different intro that starts with you under the absolute and breaking free after killing tav and taking and prism or something?

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