MySQL in Bitnami MediaWiki uses these ports by default: 3306 for "client" and "manager", 3307 for "mysqld"
I'm not sure but I think that might prevented me from running for me since I got the mysql-server mysql-client packages installed on my GNU/Linux machine. However, I solved this by changing the ports for MySQL in Bitnami MediaWiki and rebooting
Can you please change the default ports to something completely different to avoid confusion (example: 3316 for "client" and "manager", 3317 for "mysqld")?
For example, the port for Apache in Bitnami MediaWiki is 8080 (not 81) to make it clear that it doesn't use port 80-ish.