Picard was going to allow them to die until he heard the little girls' pleas for help.
No, he says no such thing. He tells Data to stop the one thing that is
against the Prime Directive - talking with the native.
That was the only
thing that Picard found wrong about the events, at any point of the story. Data being insubordinate was his sole voiced-out worry about the sorry affair. At no point does he protest against plans to save the Dremans; very much to the contrary, he arranges for such plans, arranges a conference to discuss them, and then executes them.
"Letting them die" is something Riker makes fun of, with his "fate" comments. Nobody seems seriously concerned about that aspect of the discussion.
He insists that the Boraalans not become aware of the Federation even at the point that they are all going to die in a few hours, otherwise why send Worf down in disguise.
Quite so. But this doesn't constitute evidence on what affected Picard's noninterference decision and what did not, which was the only point I was making there.
Really, there's a funny bias there if people really think TNG is about letting primitives die, when "Homeward" is the only
example of this anywhere in the show.