Hi,
This is your decision to be a witness or not, but he did (as much as you might not like it) try to harm you and your daughter. He might be remorseful now. He might blame you now. That is all about him, not you. Of course he pleads not guilty as he doesn't want to admit what he has done. That doesn't change the FACT that he DID it.
You are strong and have a baby to protect as well as yourself.
Stick to the facts about what happened. Write them out for yourself if you need to. Without emotions, what are the facts of the actions? IMHO, that is all you need to be concerned with for court, facts.