DigitalOcean App (Laravel) is Not Connecting to Managed MySQL database, times out

Question

I have a rather large Laravel 8 Project I am moving from Digital Ocean Droplet into Apps.

1. I specified all DB_* environmental App-Level Environment Variables exactly like they are in my prod .env
2. I have added that Database as resource in my App (with username/database).
3. I made sure my App is in Trusted Sources on that Database.
4. Yes, I am using public credentials as Apps do not live in VPC

I push Deploy and build goes fine until it reaches php artisan package:discover and it just times out there for 30+ seconds and deploy crashes.

If I omit database configuration altogether (i.e. empty DB_* App-Level Environmental Variables) - package:discover runs fine, however, there is no connection to db.

Even if I skip package discovery and allow build to finish, I am UNABLE to connect to database from Apps with credentials provided by DigitalOcean.

Unfortunately build never happens so I cannot even see the logs.

The same Laravel code connects to the same database with same credentials on a Droplet without a problem.

Again this is DO managed Database. I cannot really access it and mess with users. Also Apps does not have static IP address to add it to Trusted Sources. Only can be added by name.