Docker Gitlab Runner Running Flyway Unable to Obtain Connection with AWS Postgres RDS

The Problem: I am unable to connect to a Postgres RDS from a Gitlab runner via Flyway.

The Error:

ERROR: Unable to obtain connection from database (jdbc:postgresql://datacatalog-rds-stage.redacted.us-west-2.rds.amazonaws.com:5432/datacatalog
) for user 'dos': FATAL: database "datacatalog
" does not exist

What I have tried:

1. Verified I can connect locally. I am able to connect using the same credentials and jdbc url from a docker container on my desktop
2. Confirmed that the private IP address the Gitlab runner could be on, is in a source range, in the RDS security group inbound rules

Any help you can provide would be greatly appreciated.

Thanks!