Who's This? I refer you to page 31 of Who's Who vol.XIV.
How you could have heard of him: Draper did appear after Zero Hour, but under an unusual high number of aliases, you might not have realized. As Deathtrap in the mid-90s, he became obsessed with the challenge of imprisoning Superman, though his job was keeping Conduit containted. His holographic persona was used against Superboy by his daughter under the name Locksmith. And Carl would later be put in charge of Checkmate security as Castellan. "Master Jailer" DID appear at some point (2002), working for Manchester Black, though Draper was not specified as his alternate identity.
Example story: Superman vol.1 #393 (1984) by Bob Rozakis, Joey Cavalieri, Irv Novick and Dick Giordano
Of course they did.
Who else? No one else from volume XIV, but XV is just around the corner. Place your bets!