You can only attach the MFT/3-VL to the MFT/3 and use it as a router table because it has the same profile and only has two legs so that it doesn't interfere with the MFT/3 legs.
But I think it's sold in the USA together only with the router set CMS-OF as CMS VL Basic or Set.
If it's that much of an issue, your neighbor could make a pair of custom clamping brackets to join the CMS-GE to the MFT/3. Pretty straightforward project.