I'm confused as you've got the Sky box in the same extension as your hub but you are now asking for a VM installation with the TV box and hub to be in different rooms. Bear in mind that the VM TV box (V6 or 360) will replace the Sky box, so you just connect the HDMI cable from one TV box to another. If this is the case I don't see what the problem is as VM's coaxial cable can be split in the extension, one leg for the hub and the other leg for the TV box. An Ethernet cable is all that's needed to connect the TV box to the hub.
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Hub 3.0, TP-Link Archer C8, TP-Link TL-SG1008D 8-port gigabit switch, V6