That boat had radar too! I was out at swiftsure last weekend in similar conditions and there was at least one set of eyes glued to the radar screen at all times when the fog was like that, even when trolling.
WTF… the offending vessel had radar, or at least a mounted radar on their arch, unfortunately many don’t know how to use it and therefore don’t turn it on! 🙁 In any event, glad nobody was harmed in the filming of this episode!, 😎