I had the same Wordpress install issues and for me it was 2 things on my fresh Cyberpanel install on Ubuntu 20.04:
1. wp-cli was not installed. I installed it manually and everything went 1 step further during a wordpress install. Then..
The version I was showing was: 18.104.22.168 (a3d0e1171).
I removed everything like you said and reinstalled. I had to be a bit more specific about the pkg removal though, I had to specify dovecot-core, dovecot-mysql, dovecot-pop3d and dovecot-imapd a…
I have tried to reinstall dovecot with an apt-get install dovecot-mysql and it refuses because of a dependency issue with a libmysql--etc. which doesn't exist, presumably, because mariadb is what's really installed.
I don't get a choice of the OS on click to deploy Google Cloud. But the setup is listed as: