And it doesn't do that while the plugin is disabled? There's nothing really in the log indicating an issue.
So I've been able to get the printer to start when I disable TR Monitoring or if I just disable the plugin altogether. I have to think it's the stock firmware causing the issue, I'll try and get that done and report back.
Actually if you enable debug logging, restart octoprint, and then cause the error to happen, grab the plugin_wemoswitch_debug.log and looks for errors in that.