They have already killed at least 40 of their own hostages, including a family with a baby. They don't want hostages to be released because released hostages damage the narrative about who Palestinians are, they are telling the truth that they were treated with dignity and full respect.
Israel is waiting until they get full backing up by the US. There are already US troops deployed. Israel is getting the MOAB as well. The wait has nothing to do with Israeli hostages .