Antag type: Hardmode traitor

[BaneOfGiygas]

Why not call these guys traitors and the ones with equipment (undercover) syndicate agents?

Because "syndicate agents" are typically the name given to the redsuits who try exploding nukes or something. It's not their technical name, sure, but when someone shouts "SYNDIES" you're gonna know exactly what they're talking about.

Maybe something a bit more mundane. Anarchists? Rapscallions? Disgruntled employees?