So you would need to know the score of the game. All runs have a bearing on the outcome of the game (until they don't such as the last inning scenarios).
Correct; that's why DI is rare. An example of DI:
In the bottom of the seventh inning with no
one out and the winning run on third base, the batter taps the
ball to the pitcher who makes no throw to first base to prevent
the winning run from scoring. RULING—Credit the batter with
a fielder’s choice to gain first base and an additional fielder’s
choice if she gains second base due to indifference.
i.e. only run at third matters; hence defense is indifferent to batter advancing to second, as it has no bearing on the outcome of the game.