Nothing in there for any IPs with 172.whatever?
Only thing I see there of even mild interest is a second bridge truenasbr0 but I see no way that it conflicts with anything at all really.
I’m sad to say that your issue is very different to mine & that I’m not sure if I’m useful in helping. Hopefully the info you provided is useful to someone smarter than me.
I do notice that what you’re describing seems very similar to the following post due to the beta version - they also have a workaround: