I appreciate that this was dealt with, but as a parent I have the right to know that this occurred and quite frankly should be made aware if my child is physically antagonizing another child. What happens if this comes up somewhere else and it is reported to the parent. They may become defensive thinking that this is very out of character for their child, when really it isn't but having that information withheld from them means that they are oblivious to the true behaviours their child is acting out in. Also there are things that the parent can do after the fact. They can reinforce appropriate behaviour at home through play and story time and the incident of poking another child with a fork could be a reason to discuss feelings, bullying and what it means to treat others with respect and appropriately. It's not about telling the child off or disciplining them, but acknowledging what happened and establishing that it's wrong and why they felt the need to do it. You dealt width it, but I think it is important that all caregivers back each other up so the child learns consistency and that's why the parent should know what happened.
If I find myself constantly reporting negative daily incidents with a problem child, I always make sure I tell the parents the good things to and I reinforce to them that I am not worried, and that I am sure it is a normal phase of childhood development and behaviour but that I want to keep them in the loop and let them know what I am doing as the child's dcp to help them overcome this. That way I have eased their fears that their child will be kicked out or that he is actually "bad" and it quite often will prompt the parent to tell me if other incidents have occurred to see if their is a pattern or if their is any change in home life which may be instigating this behaviour, which ultimately may help me to carry out behaviour modification with more success.