I mean ask (or more: convince) your boss for permission to make the code publicly available.

Ask your boss.

I tried editing my config.yml as the guide suggests but the problem persists. The problem seems to be that I’m using MariaDB instead of MySQL (pdo_mysql is compatible with MariaDB). Is there anything more I can do or should I try installing MySQL?

EDIT: Purging MariaDB (Debian repo ships this instead of MySQL) and reinstalling it with sudo apt install default-mysql-server fixed the problem. Thank you.