but where are all the fics about his relationships with Jack and Sydney? I'm bewildered that Sloane/Jack friendship fic, even one-sided stuff that paints Sloane as solely the evil betrayer, is virtually non-existent. It's the most interesting relationship on the show!

Agreed. And you can't tell me that if Sloane and Jack were played by younger actors, there wouldn't be fanfic galore. Ageism and shallowness on the part of fandom is really my only explanation.

(BTW, I take it you've read kangeiko's as well then?)

Denial fic, or rather fix it fic, is especially easy with everything this show has provided in terms of escape routes. There are canonical doppelgangers (who's to say Irina in the last two episodes was any more Irina than the one Jack killed back when was?), Jack when blowing himself up was in cave full of Rambaldi immortality juice, and as for Sloane, he had a canonical breakdown after Nadia's death (the writers, asked whether Nadia's ghost that Arvin sees is meant to be genuinenly supernatural, have said no, that's Sloane beating himself up), and given that plus all his other issues, one can certainly explain his actions and come up with a scenario that has him and Jack escaping from the caves.