And he said unto me, Son of man, can these bones live? And I answered, O Lord GOD, thou knowest.
The bones in the valley were so dead and so dry Ezekiel couldn't see how they could live. God can do anything, but it would be God if these bones ever arose. The Bible does not say that God told Ezekiel they would live, only that God told Ezekiel to preach to the dry bones that they would live. Behold, they did live!
It is not our work to pick who may or may not be saved. It is not our task to determine who might and might not be called of God to salvation. Debates over what is and isn't election and who is and who isn't the elect are fruitless. These are realms that belong only to God. Our task is to preach to people the way of salvation. Some we may never have imagined will get saved. Some, we will be surprised to find, were not saved.
The result of the preaching of the Word of God is up to God. Our job is to see that the preaching gets done.