hmmmm thats interesting - the other socket is a standard aerial connector but the cable end you show is a F type connector that could be the input cable - that comes in behind that box - you could remove the box and look whats there
but for a £1 or so get one of these and try things
https://www.diy.com/departments/tristar-data-cable-coupler/571706_BQ.prd
put that in and then the isolator cable that came with the hub - power it up and see what happens - whatever happens you will need to activate the hub - the number should be in the quick start pack
if that works great if not book a tech
____________________
Tony