Each UC has their holistic criteria, so not getting an acceptance to a “easier one” does not mean you won’t get acceptance to a “harder one”. Hopefully you had other safeties that you applied to.
The top 9% means you’ll get into a UC of the UC’s choice - most like UC-Merced.
I don’t think the UCs talk to each other, but there is definitely some shared information that they have access to.
is the GPA that you stated a UC capped weighted GPA?