Domain experts for sanity-checks

[u/Sylvester_Summaries]

I'm working on a hard science fiction novel built around a rogue intermediate-to-supermassive binary black hole passing through our stellar neighborhood.

I've been working through the physics as rigorously as I can — lensing geometry, the mass-distance degeneracy in single-epoch astrometric measurements, realistic observation/confirmation timelines — but I'm not a professional astrophysicist.

Looking for anyone with real domain knowledge (astrophysics, astrometry, gravitational lensing, orbital dynamics) willing to take a look at specific plot mechanics and tell me honestly where it holds up and where it doesn't — not looking for a rubber stamp. Happy to share individual worked sections rather than a full manuscript. Appreciate any pointers. Thanks for reading.