Self hosted trial connecting to RDS fails


I installed the self hosted retool trial on my local machine however I am unable to connect to any AWS RDS databases.
I normally connect to these databases via a local IDE and through our VPN connector. When configuring this on my self hosted local retool, I keep seeing testconnection failed
Error: request to http://db-connector:3002/api/testConnection failed, reason: connect ECONNREFUSED

Any help would be greatly appreciated!