I think Lolth will not forgive her for betrayal, so when she opens her eyes to the absolute
Who knows? Most people do not seem to know this but Drow atually do not need to have 'red' eyes.
And apparently they only have the red eyes because Lolth favours them in some way for their mentality and actions.
Lolth probably thinks it is cute that a Drow has gone "renegade" but is still acting like an evil, cruel Drow Mistress should. She is a cruel Goddess supporting ill will and manipulation after all.
I think she would be more enraged with Minthara if she suddenly becomes a "surface Races lover" and wants to do good things overall.

But yeah Drow can actually lose their red eyes if they denounce Lolth and choose Eilistrae instead.
Very ni~ce if you see a Drow with eyes that are not red it is kinda a seal of proof that they are most trustworthy.
Until the Lolthsworn Drow learn to hide their eyecolor that is.