Question

Once again Netanyahu is lying. He said that his father begged President Roosevelt to bomb the extermination camps, and Roosevelt replied, 'Over my dead body'—they will not be bombed.
I understood that leading historians were asked about this, and all of them were adamant that it never happened at all—not even remotely.
Fine, so he's fantasizing again…
But it raised a question I've thought about many times. (A request to bomb did reach Churchill; he ordered it, but the order was not carried out. In the U.S., the highest-ranking official who received such a request was the Deputy Secretary of War… and he answered that the needs of the war did not allow diverting pilots there. There was, however, a Jewish boy who managed to escape the killing valley, advanced until he reached the air force of one of the Western countries, connected with the pilots, touched their hearts, and tried to persuade a pilot to bomb the place. That wasn't practical, so at least to drop leaflets saying, 'We are coming to save you, hold on'—if only to save the numbers of Jews who were committing suicide in the camps out of hopelessness. He couldn't persuade them. Seeing that this was the situation, he pleaded with and made clear to his pilot friend that this was his final request… He deliberately committed suicide by throwing himself into a military truck. The pilot broke down because his friend had killed himself because they were not being saved, and he did indeed manage to persuade them to make a detour in order to drop such leaflets. They reached the prisoners in the camps, and many understood that their salvation was near, did not commit suicide from despair, lived to be liberated, and some of them came up to Zion.)
Is it permissible according to Jewish law to bomb the camps and the gas chambers when that would certainly kill those who were there, but on the other hand would save the Jews next in line?
As for those inside the chambers or on the way there, the intuition says that in any case they have already been taken to death and are considered as already doomed.
But those in the camps? (Under the conditions of that time it probably wasn't possible to be precise.) Some of them would in fact be saved if the camps were not bombed.
Is it permissible to kill them in order to save those who come after them in line?