@Meo not defending him, but I don't think he knew she hurt herself on on purpose. Seems like he was purposefully distancing himself, and he does it to Zeke as well. If you look at what he said about the airship he gave her a pass because he said he did similar things due to the pressure as a kid.
What that doesn't explain is his behaviour in the original timeline, he is clearly traumatised by her death, yet he let her be executed.