as far as I know the IOS stacked VLAN routing example you gave works with Cisco routers only, not with switches. Switches usually support Q-in-Q only as a layer 2 mechanism (I have checked this for EXOS, (Extreme) EOS, Cisco IOS, and Arista EOS recently).
You might be able to use two EXOS devices, one to de-encapsulate Q-in-Q and another to implement routing, using VRs to separate layer 3 networks. But that does not scale, as you would need one cable (untagged port) per routing interface in general (i.e. with overlapping customer VLAN IDs).
Port specific VLAN IDs might help to get around the 1 port per layer 3 interface problem, but those cannot be combined with a layer 3 interface in the translated VLAN on the same switch, thus you still need at least two devices (I did not check the possibility of combining Q-in-Q and VLAN translation).