I could have sworn on some older projects early on in the DN’s life if you saved a patch it saved the unison settings for the track as well? It doesn’t seem to know (possibly ever). Did I imagine this?
If I did imagine it, this should def be a feature addition. I’ve taken to putting the settings in the patch name (U246) for example ((Unison-voice count 2-8-DetuneAmt) or just (Uni) if it benefits from a general setting not entirely dependent on specifics.
Simply put: yes.
That’s the culprit with every project (global) setting. Unison is quite special in this way. While it alters the sound heavily and should therefore be part of the patch, it also alters heavily how the whole setup behaves. Think about a carefully crafted pattern where you dial in a unison using patch on a track just for variations, but without knowing: instant bug report … 
Yeah I figured that may have been why It wouldn’t have been included or (removed had it been there initially) boooooo.