did you actually ""see'' that he was the one that kicked your ds? personally, I don't just give my number out to anyone, if she says she wasn't his mother, then what do you expect? even if she was, she probably knew you'd ring her.. maybe she thought you'd harass her and she doesn't want that.
playgrounds are playgrounds unfortunately, my dd has been kicked in the head and so forth, and if i haven't had much of a response from the parent, i tell the kid off myself and that's that. i leave.
good to hear his eye isn't seriously damaged, it's scary when these things happen. unfortunately we sometimes think other parents are like us, but they aren't and it's dissapointing.