Lae'zel likess strength: The druids and the tieflings a basically cowering in fear, the druids want to hide, the tieflings are mostly no fighters. The cultists are proactive (let's go and attack the druid grove), which is something, Lae'zel can get behind, because it is, how she was raised. She doesn't always approves of evil things, mostly, she approves if you show strength and resolve or not helping someone weak, because the weak have no place in Githyanki society - for us, that is evil, for Lae'zel it's Tuesday.
This ... Plus the fact that i bet Lae'zel is quite sure, that if they (read as: Githyanki nation) want ... they can wipe out the whole Absolute cult, with their Goddess herself, in one bussy afternoon.
So there is really little to no reason to wonder about how much pro-, or anti-gith busines of this cult is.