Technically possible, but boring.
In the database you will find a table called picklog with the date and time of obtaining that item. There will be described the type if it was dropped by monster, NPC, or by some command.
Filter exploit dates and times, and the type of (monster, npc, command). Get account ids and delete the items in table inventory, cart_inventory, storage, guild_storage.
It won't be 100% accurate, but it will give you a north to adjust.
Sorry for my English. I hope you understand.