AOL is the only Feedback Loop that I am aware of that frustratingly redacts recipient addresses. As such, unless it is a Bulk Email or Newsletter that has a SmarterMail UNSUBSCRIBE link included in the sent email (we require all Bulk Email or Newsletters contain their Physical Mailing Address and UNSUBSCRIBE information in the Footer Messages along with the SmarterMail #UnsubscribeLink# tag which contains their email unredeacted by AOL's Feedback Loop) then the only way to find the recipient is to get the sender + time from the Header info of the attached email and find the recipient in your SmarterMail DELIVERY logs (you could also use the SMTP logs although they might be off by a few seconds which is fine for individual emails but probably like finding a needle in a haystack for large bulk mailings such as newsletters).
It's important to note that it is common to get Abuse Reports from falsely-tagged emails. Our Mail Servers primarily send out Order Receipts and Shipping Status Updates from eCommerce sites and we get about 2 or 3 of these a day that are flagged as Spam. It is perfectly okay to ignore these (whereas if it is a Newsletter or other Bulk Email it's important to UNSUBSCRIBE them right away upon receipt of the Abuse report) as every provider expects a certain percentage of falsely-tagged emails. I always check the email though just in case an account has been compromised and may be sending out Spam or a customer is genuinely abusing the ToS.