Recalling Email Message

Scenario:
I received an email as a CC that was sent to multiple people. I then replied to all. (no problem so far). Then my boss wanted to just reply to me so she choose reply and it only showed me. Then she needed to recall it so she did and resent as private (again only to me). When she was done she received message recall failure to all of the people that was in the original email even though she wasn’t sending the reply to them. WHY? Did the reply actually go to everyone even thoughit doesn’t show on the sent? or did it just show recall failure because they were on the original message even though she wasn’t replying to them?