If it was me OP, Id make a dash for Gate 138 Thats where the TLV goes out of. Im sure you wont be the only person since this coming Shabbos is @ 4:30pm so what are all those on the 84 gonna do??
If delayed then Im sure by any Intl Gate heading To Europe theres a great chance that at least 1 Jew will be on it or passing by
Ive in yrs past lit by the check-in counters, always asked 1st and asked that they please not extingush them before x mins, and I was usually told why extingush them at all before they burn out
wanted to add, Gate 138 is blocked off so you wont beable to access the counter area but should be no problem setting things up there or on a table near to it . Follow the signs for Gate 128 so you will be by where they enter and exit to access 138, theers only 1 way in and out