Decided to bring the best and brightest that I know of together to try and solve some desync issues... and even though we didn't solve it right away... we did figure it out!
https://forums.factorio.com/viewtopic.php?f=7&t=44344&p=256104#p256104
It was a vanilla thing! Turns out fire is bad. Don't teleport fire. Its... *bad*.
Special thanks to everyone who helped, including the people in Twitch! We identified, reproduced, and hopefully will have gotten fixed a *vanilla* bug!
And more importantly we can use AAI mods without desyncing :)