I am very happy to report that it has been about 14 hours with 100% connectivity, no device resets with the device publishing 2X per minute and I haven’t had any issues. At this point, I suspect the root cause was using Serial.println() and Log.info() within the same project. I think the race condition or timing just happened to be perfect around the Log.info within publishQueue.publsih() and the serial.print() I used just before and after it. Adding the delays just happened to change this timing enough.
This has been yet another reminder to always read the docs!
Solution: Change all Serial. Print, Serial.println, and similar instructions to instead use Log.info (or similar based on desired logging level)
As discussed here: From here: https://docs.particle.io/reference/device-os/firmware/boron/#serial