You won't see anything with a multimeter.
Unless a coax has been physically disconnected from either the Foxtel street cable or satellite LNB, it will still be 'live' eg: carrying signals.
This is of course providing the coax cable was connected to Foxtel previously and not just a 'pre-wire' for possible future connection.
You would need a receiver/signal meter to test if signals are present and a valid, activated Foxtel smartcard and suitable decoder to display the encrypted channels.
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