FrogReaver
The most respectful and polite poster ever
Just one more follow up. Sometimes PCs fail. Sometimes they don't catch the bad guy, sometimes the plan doesn't survive contact with the enemy. Sometimes the paladin has survivors guilt or had no chance to save the innocent and must spend the night in prayer in penance or seek absolution from a priest.
Failure makes victory something special. Finally defeating that villain that sacrificed that child in order to get away is something to celebrate.
My way is not the only way to play. If you and your players want lawful "death beforedishonorimperfection" paladins to be a thing there's nothing wrong with it. Just don't be surprised when people say that paladins must be lawful stupid.
Paladins can fail all the time. It's the how. NPC snatched and carried off while under your protection, then you did your best. Dragon tells you to choose either yourself or the NPC for him to eat then that's a problem. It's how you've set up the scenario to be principles vs life. That's what creatures lawful stupid characters. Don't challenge the characters principles with their life. That's the simple solution.
If you insist on setting a non-pragmatic lawful good trap then don't expect people not to blame you the DM for creating the lawful stupid behavior.