Yes it not an IEC Mains cable.
Instead of extending the mains cable and having 2 sets of wires out of either side of the telly then why don't you extend the HDMI cable and send that in the direction of the mains cable?
Personally i'd take the whole mains cable to an electrical shop and show them the connector and find the part you need or just extend the mains cable using an extender cable meaning you don't cut any wires like below?
http://www.connevans.co.uk/store/vie...DAAC8D?id=1468