Welp, I found some NPRs who spawned on a weird planet. Namely, this planet has all 11 minerals, yet the game is telling me it's a gas giant. I was wondering why I hadn't been able to find their homeworld...
So now I'm allied with a race which is, for all intents and purposes, non-existent.
The good news is that one of the moons of their 'home planet' had a colony cost of 0!