Reading your stuff thinking maybe of testing Frigate on the Zoneminder box which is running Ubuntu 20.04 these days. Been using Zoneminder for many years now.
Running BI on same hardware with Windows 2016.
Goodbye Zoneminder
I have never messed with blue iris because I don't like running windows boxes if I can help it. It should do pretty much the same as deepstack though. So far frigate has done wonders for me. There is a docker image that you can use to test with. Configurations are still done in YAML but if you mess with home assistant it's not difficult. It's actively being worked on and the dev is very active in the home assistant forums. Good luck getting a coral if you decide to stick with it though. Mouser isn't shipping USB ones till April of next year, they occasionally pop up on other sites. There are a couple of youtube videos that go over it from MostlyChris and Digiblur. You can really go off the deep end with what Linus tech Tips is planning to use frigate and doubletake for. I am using double-take to run facial recognition too and they make a crazy powerful paring especially with home assistant. It's why I am really wanting to capture button presses and see if I can access the speaker on the DB1 from Onvif or other means to use home assistant to play pre-recorded messages as the app is a little slow sometimes. Frigate usually gets a hit as soon as the person steps onto my property, pops up a moment later on my google home hub or plays the announcement on my google home speakers and I usually have the app loaded up before they can hit the button causing even more issues when the call tries to come through when I already have the app open.