It appears that the octoprint service does not work if the initial user is not the default "pi" user. Using the Raspberry Pi Imager, you have the option to set the user credentials and I have a default that gets set on all my new images. I'm not sure if this is actually an issue with octoprint or this particular installation of octoprint, but I thought I would bring it to your attention so at least a note could be placed in the documentation.