Could this happen in say, random adventures? Both the Asura and Charr are very particular folk, but could a travelling Asura help out a wounded Charr and the two become adventuring buddies?
Asura seem to REALLY care about their brilliance and how others see them, so it's like "go to uni and make something or you're dumb."
Meanwhile Charr have a whole society based around warbands, or you're a gladium. I haven't heard about many "adventuring/lone wolf" Charr, or even Asura really.
I expect these "fateful encounter" type of thing to be more normal for a Norn, since their whole thing is to craft your "legend" and do whatever you think will make you awesome. Same with humans and sylvari who are very free spirited.
But yeah, do we have cases like these in game?