Ran into the same issue. Brand new Workhorse, plug in Octoprint, click connect. Workhorse (Marlin) resets, and hotend temp is set to a random high temp.
Shut everything down. Started the Pi, when it finished booting and tried to automatically connect to the printer (presumably), the printer reset and came up with a hotend temp over 300 degrees.
Luckily I was watching it because a friend just got the exact same setup and ran into the exact same issue.
I don't notice anything interesting in the logs, except that the Pi is undervolted. I'll find a larger PSU and try again, although this same setup has been working fine on a Lulzbot Mini for months. If there are any loglevels I should change, any information would be appreciated.
Not sure if the issue is with Octoprint or on the Marlin side, but there should be no reason this thing should try and immolate itself.
octoprint.log (52.6 KB)