Do you know where the doxxed info ultimately originates from? It turns out that the archives leaked account names. Try Googling what happened to volth on Github.
On the network layer, I don't know. But on the WWW layer, archive.today operates accounts that are used to log into websites when they are snapshotted. IIRC, the archive.today manipulates the snapshots to hide the fact that someone is logged in, but sometimes fails miserably: