Australia and New Zealand don't really have any use for a cable to the Falklands, they are already well connected on multiple routes, other than SE Asia there are links to Guam, Japan and Hawaii as well as direct to North America.
Wiring the Falklands without touching Argentina would be difficult. I don't see how a route to the Pacific could be viable unless it is a real "island hopper" Starting in New Zealand and connecting practically every island country in the South Pacific from Fiji to Easter Island then around the Horn to the Falklands. Even then it's economic viability is far from secure. Quite frankly a Falklands to South Africa link makes more (but not much more) sense.
A satellite link is a lot easier, more scalable and much more difficult to disrupt by hostile action.
Wiring the Falklands without touching Argentina would be difficult. I don't see how a route to the Pacific could be viable unless it is a real "island hopper" Starting in New Zealand and connecting practically every island country in the South Pacific from Fiji to Easter Island then around the Horn to the Falklands. Even then it's economic viability is far from secure. Quite frankly a Falklands to South Africa link makes more (but not much more) sense.
A satellite link is a lot easier, more scalable and much more difficult to disrupt by hostile action.