The OP describes a situation using words like “shocked”, “mortified”, and “street kids”, but the actual details provided in the post make it very unclear what exactly happened that was a chillul Hashem.
Then we have two posters fly into the discussion from out of the woodwork putting down Yeshiva students – practically as a whole – with Grandmaster striking back by putting down public school students.
I have the feeling that something disingenuous is going on with this thread.