You could get a technician to install, call the pre-installs team on 0800 052 1734 8AM- 9PM Monday - Friday or 8AM-6PM Saturday and Sunday.
An easier option is to just get a female to female F connector, available from B&Q, Amazon and others. You then just do this:
1) remove the attenuator from the existing cable, plug it into back of hub
2) plug new provided cable into hub
3) other end of this cable, connect the female to female F connector, connect the other side of this to the cable from the wall.
Wiring should go :
cable from wall ——->female to female F connector ———-> cable to isolator——-> isolator ———> attenuator———Hub
There are 10 types of people: those who understand binary and those who don't and F people out of 10 who do not understand hexadecimal c1a2a285948293859940d9a49385a2