If I remember correctly, I think Zoya was also in the same year as Amanda at Athena Academy. So the girls would have known each other at school as well! She really likes Alex, so she'll be friendly to both Bash and Zoya. :D
And yes! I feel like Amanda definitely would have been aware of Finnley, at least. In fact, maybe that first year when she was kind of struggling socially, she could have reached out to Finnley for some advice on how to adjust after skipping grades?
Amanda has MANY feelings about Rhys and Lyllia, but she mainly keeps them to herself or between her and Hunter. She's always polite (but distant) whenever they have to interact, and she never badmouths either of them in front of the kids. She would do anything for Rose and Ian wants to make things as uncomplicated as possible for them. So essentially, yeah. She'll leave Lyllia alone for sure.