Since you have made the DNS/Alias entry at the DB side to point back to the new DB instance with the existing connection which are configured in EPM, I think it should be fine.
It's better to log an SR with Oracle, to know implications about this change. Because, on-going, if you find any issue, we can't trace the changes which change is causing that issue.
When you are pinging Host AAA, you mentioned you are getting IP Address of BBB. I think, this is fine, because ultimately we needs to get connect with IP Address.