While you should understand what is in this tutorial that has been offered, what it covers is quite basic compared to the Q-in-Q-in-Q config you posted.
@orangetekcy can you explain what the intent is?
Are you just relaying frames that happen to have stacked frames from one sfp to another?
Before you get your hopes up, I won’t be able to help, as I have never used Q-in-Q, and the only MikroTik router I have is a low end hEX S (5 port + 1 SPF). But I can recognize that this config is more complex than those help articles deal with.
What version of ROS is running on the CRS309?
My suggestion is to go straight to the Official Help
Bridge VLAN Filtering good overview
Bridge VLAN Table very detailed information, although there are some places where they don’t specify whether bridge vlan or bridge port command should be used, but you can determine this by trying and using tab completion to see possible completions.
These youtube videos may be helpful, I would start with the first, then the second.
Mikrotik VLANs - CRS3XX Step by Step - Mikrotik Tutorial The Network Trip youtube video.
Switching, VLAN, QinQ in ROS 6.41 Onwards and their application to CRS 3.xx models. MUM India 2018 slides