I've seen from this post (https://firebase.blog/posts/2022/09/announcing-cross-service-security-rules) that you can validate Storage rules against Firestore data, however, I can't find any information if you can do it for Realtime Database.
Riiight at the bottom of the post, the last paragraph says:
So there you have it. That’s our shiny new feature. Try it out and let us know what you think. For the next milestone, we plan to support cross-service rules queries to the Realtime database! Stay tuned!
So.. not yet :)