I don't consider Victor's explanation a good one because you can turn off the sat phone from the cockpit without having to resort to such extreme shenanigans as isolating an entire bus.

As for the A/P being available when the Left A/C bus is isolated, I think we covered this in Season 2 Episode 1; we found that actually almost everything is still available when the Left AC bus is isolated, in contrast to the extreme loss of function that occurs when the entire electrical system is isolated, which to my mind made MenTour Pilot's scenario really ridiculous.

Not so say that a suicidal pilot isolating the left AC bus makes very much sense, either; as Ron Rogers made clear, isolating the left AC bus is something a 777 would never contemplate without a checklist telling him or her to do it.