Thanks for the log The server is indeed running on the old version 0.6.5.1 (you can find that information at the very top of the log)... not sure why SteamCMD doesn't update it properly (even after adding the validate parameter) I would recommend to try to delete the server files then, as described above (just keep the Worlds folder and maybe the "Permission" folder and the server.properties file), then run SteamCMD again.
OK. I figured it out. My brain was the issue. I figured SteamCMD would update the directory I was in, seeing Rising World Unity Server already there. No. It was updating to the default location in ~/.local/shared. Ugh. I did the force_install_dir in SteamCMD and that worked. Thanks for your help, Red.