Crikey, how awful for you and dd. I'm so sorry.
These things DO happen. My then 2yo ran in front of a van a few months ago. He was fine, the van was doing about 2mph through a crowed pedestrian area.
I wasn't holding onto him, he ran off, didn't see what was in front of him and bang.
Lots of gasps and people wanted to help but he was just a bit surprised and cried for a moment.
It could have been terrible, but the poor bloke driving could not have done anything other than staying at a very slow speed with hazard lights on etc which he was already doing.
In fact he stopped a split second before impact.
I took it upon myself to reassure him several times that it was not his fault at all. No one called the police thankfully.
I hope he isn't feeling as bad as you are 