I think it's definitely possible. Not in the perfect world sort of sense where everyone make up and become friends, but in a more realistic sense. Szeth owned the murders in the end. He took full responsibility. I doubt he wants to continue on the path of murder and assassination(even though he's superb at it and I want him to). There is also ways he could be extremely useful. While I agree he would bring a bad rep to the knights radiant, he could be utilized as a black opps( or white opps ) operative, which he would excel at, though he may not want to. And another way he could prove to be invaluable would be to tell them about Taravangian. That right there should earn him some slack. With Odium and the Everstorm and the voidbringers, Kal and co. might just have to suck it up and work with him.
But then again, Nalan may have his own ideas...