I can certainly understand you being upset. It seems odd that both were lost in the same outting...did he explain what happened to them???
Personally, it would bother me a lot more to hear of losing birds to predators who've broken into the coop - because that says that the coop was NOT a safe place (and a coop should be a place of security). To lose a bird while free ranging usually says that the caretaker wanted to make the birds happy by giving them freedom and space...