Here are the facts, shkiah in TLV was 4:40:38 as per Hebrew calendar. As per flight aware the flight took off 11:46.
If you look on the history of flight LY02 when they have the 747 for it, you can see that a week before, Nov 8 the flying time which includes taxiing was 9:49 which means from gate departure till gate arrival.
From 11:46 EST to 4:40 IST is 9:54, that is even more time as the week before, which it was 9:49 including taxi before takeoff which is a substantial amount of time.
I am sure had the flight landed in TLV they would have got priority to get to the gate, plus sometimes ATC can give a faster route.
To conclude, this whole fiasco and the double chilul shabbos could have been avoided. If the plane reaches the gate before shkiah, people would have had no problem al pi halacha to leave the aircraft to the airport.
ElAl could have arranged a nice shabbos in one of the Lounges airside, plus you understand the Israeli government is more lenient to just have the whole group escorted to a large area till moitzai shabbos. They could even make an eiruv in the entire airport etc.
I am not looking to take away blame from Elal as they we're wrong with delay to begin with, and they should have given an option for people to reschedule for Moitzai Shabbos before the boarding. That wouldnt delay the flight any longer. If anyone chose to stay, he can't complain that he is arriving 2 minutes before shkiah.