There are many ways to increased challenge in and out of school that don't depend on DYS. Enrichment, extracurriculars that are demanding, sports, etc., can all help your DD learn to handle challenge.
I'm thinking that it would be better for her to be in DYS too, if she qualifies. I have yet to really see what it is all about as he just qualified. I think it would be a self esteem boost if they both are particiapating in DYS instead of her feeling left out. I have just the 2 children. I would also like to find ways to challenge her more in school. I do lots of challenging things out of school.