Regarding auxiliaryProtocol's identity...
The black text, the white eyes, and the fact that he seems to be at one of the post-apocalypse terminal might peg him as a carpacian exile, specifically a Dersite. He may have shared a friendship with Jaspers and got to know him over a period of time in the game. However, unless the carapacians are a universal constant, he's not gonna be Jack or any of the other agents we know from Homestuck.
Rather, he is the Guidestuck version of the hat we briefly took control of in Act 4 to see what Dad Egbert was up to.
Hal Harley and Isadora Egbert are Bec and Quinn's ectoparents
Their apparent "Official Couple" status could be foreshadowing to this. Obviously, this would mean that Quinn is Bec's paradox sister.
Or he will turn out to have been Evil All Along
and actively sabotage the session right under everyone's noses. Either way, with canon stating that Cal's very existence ruins the lives of anyone he shares a universe in, it's possible that he'll turn out to be a pretty nasty little bugger...
- Perhaps, concerning certain things in canon, he will turn out to be this Comics version of Caliborn