There genuinely is only one way you can do it
give the ev admin full access to everyones archive and then use search.asp to find the item then delete it through search
another way to identify them through the db, is if you have discovery accelerator, if you can run a search against that particular email and then put it on a hold.
after that, run a query linking savesetholdgroup, savesethold and saveset, that will give you a list of the items on that particular hold, export it to a CSV or excel spreadsheet
remove or delete the hold, then you can either delete the items out of saveset table but is not recommended, you can then use vsverify to clean it up
OR when you have the list of savesets you can format some deleteo2k.asp requests using the savesetID's vaultID's
simplest way though is through search
https://www.linkedin.com/in/alex-allen-turl-07370146