Hmmm, sgcbundy, this is a weird one. I'm not sure a factory reset would assist, but I also don't know what that particular error message indicates -- network error? Provisioning issue? It's hard to tell, but my first guess wouldn't be a device problem. It sounds like you've done a bunch of troubleshooting already -- great job! When you first got your Pixel, did you set up the BYOD APNs on your own? Do you think anything has changed that might have altered something there?
Are you still seeing this now; or did it clear up? If you're still getting errors, I think the next recommendation I would make would be to reach out to our internal teams with account access -- specifically, Tech Care -- and have a ticket filed under the Roaming category (our reps should know to select this when you provide your address, but it doesn't hurt to mention it to be careful!).