After some tests, I really don't know but it works. The issue is with the hostname that AWS gives us.
Steps to fix the issue:
Register a SIMPLER hostname (HOSTS file or DNS), like: 22.33.44.55 simpler.domain.com
SSH into the server and execute:
sudo /opt/bitnami/apps/wordpress/bnconfig --machine_hostname simpler.domain.com
...
PROFIT!
Maybe the issue it's related to "-" characters on the hostname that AWS EC2 gives us, otherwise I don't know what could be. I just know it WORKS!
Hope it can help someone! :-)