proxy01.phx2.fedoraproject.org,apps.fedoraproject.org ssh-rsa AAAAB3NzaC1yc2[...]
Either the file needs to be updated with the correct key or the hostname is wrong.
There should be no entry for apps.fpo, but there is one entry in /etc/hosts, making proxy01 believe it is apps.fpo:
$ grep apps /etc/hosts
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