Hmmm. I'm no gcloud expert. But here's where I'd start looking.

What version of FusionAuth are you running? Can you connect to the mysql database in gcloud directly? Are you seeing any errors in the FusionAuth log files? Can you connect to where FusionAuth is running and try to connect to the database directly? Is the issue the connection or that FusionAuth isn't running as a privileged user? If the latter is the case, silent mode might help. You can run the table create statements directly against your database and FusionAuth will notice that after starting up.