I don't think he was realising how far he had pushed her. He surely didn't expect to be attacked with a knife. Kapoor was reckless and she didn't think that inviting Karama to their quarters would be anything special, she thought that "all has been fixed". He went there, because he didn't expect Ullmann to take everything so seriously. He thought once he stopped paying any attention to her - no more problems.
And then suddenly this. I'm sure he was surprised. He didn't want to provoke Ullmann, so he just backed out and left without a word. Maybe that was the moment when he realised what his "jokes" really meant to her, that she really believed everything he had said and she still
If he expected she would tell Jarol? I don't know. I don't think so.