I think McKathlin is reading too much into the cast page (it is after all attempting to condense entire characters into a name, an age, a job, an orientation, and a pun), but otherwise spot-on.
It's been two weeks in-story since the comic began, but it's been an action-packed two weeks. I don't really know what the usual minimum time between meeting and forming a relationship is, but even if two weeks is abnormally short they've spent a lot of time together and had a lot of powerful shared experiences (see also: every single plotline in this comic). I can see no catastrophic life failure resulting from any make-outs at this point in time, unless Max gets involved.
It's really a question of what they want to do at this point.
Ellen: Drunk, offering quasi-sex as "apology" to Jamie even though he already accepted her verbal apology. I'm usually pretty oblivious to that sort of thing, and even I'm picking up on it. She liiiiikes him (read in mocking 10-year-old voice). Interestingly, note her distinction between "sexual" and "romantic"; it's clear she approaches the sex/romance divide from a completely different direction to Max, and probably from a completely different direction to Jamie though I don't have enough data to confirm that one.
Jamie: Sober, stressed out from his lawyery ordeal, mentioned an "instinct to wait until marriage", fairly uncomfortable with Max urging him on, and reacts to Ellen's offer with a sarcastic response that doesn't actually acknowledge what she said. He may or may not liiiiiiiiiiiike Ellen, but he's not going to act on it tonight.
Sum total plot prediction: Ellen makes more blatant advances on Jamie, Jamie turns her down (explicitly or not), Ellen wakes up the next morning to a pounding hangover and the smell of Jamie making fruit crumble for breakfast, has an "ohgodwhathappenedlastnight" moment, slight awkwardness in the short to medium term, story arc comes to a close, later story arc brings it back up and either has Ellen and Jamie enter into a committed relationship or has some traumatic event that makes them never look at each other that way again.
... in accordance with the prophecy.