Hello Community, got another riddle for you ... this is a strange one because it's a custom implementation but I hope it's feasible. Will start with a Diagram :

Considering the diagram above and traffic flow from left to right, is there a way for the middle device (QinQ Capable SW most probably) to encapsulate the same Customer VLAN tagged frames (on the left) into secondary dot1Q frames, creating the QinQ frames of the scenario depicted on the right Physical Connections are as shown ... single link between devices.
Thank you all in advance for any feedback and ideas