The whole point that a match win over a modified win is that the winner won by more than one ship. Now since not all ships are equal and some ships are worth more fore example killing a Fat Han is worth way more points than killing an Academy pilot you have to go by MOV to determine how much each kill is worth. A modified win says that a person theoretically won by 1 ship the lowest point cost be it academy pilot, bandit squadron pilot or bynree pilot. If the margin of victory is less than 12 points then you really can't say that the victor won by one kill more thus a modified win as it was close but it one person happen to kill higher value ships.
However that is the whole concern is with MOV and all the meta talk right now as amount of damage done is not necessarily equal to victory points. Point fortresses help to retain the amount of points so that even if only 3 TIE fighters are destroyed and the Fat Han is at 1 hit point left. Sure the Fat falcon took more than 9 hits but it counts as 0 victory points for the match. Thus the full win and 5 match points go to the Fat Han.
You keep dodging the fact that we have absolutely no problem determining the winner as being by 1 if it is an elimination round. If it good enough for the important part of the tournament, then it should be good enough for the rest of it, so why have modified wins at all? So why persist with the belief that you "have" to win by the completely arbitrary "more than 12". At the most important part of a tournament we precisely do not care if you won by 12 (otherwise we would have with some form of overtime or untimed matches).