The desired reading of the phrase "humanitarian pause" is to convey "temporary ceasefire to allow for civilian evacuation," but knowing the US & Israel, it probably means "ceasing what miniscule humanitarian aid makes its way into Gaza."

The IDF has already killed hostages in their indiscriminate crossfire. And seeing how the released hostages have openly spoken to the press about being treated humanely, I don't think they care all that much about getting those who remain out alive. It would be more effective for propaganda to let them be martyrs than risk even a slim chance of countering their narrative.