Sam,
” So too here. Whether or not this precise story actually happened is irrelevant.”.
That may be true if the question was “should these boys have helped this girl”. However, that was not the question, or actually the statement by the OP.
The OP started of by saying, effectively, that these were horrible bochurim, how can anyone dare argue with her take. Which can’t be answered because no one knows the circumstances, the story as written has too few details. (Nor did the OP clarify if the girl stumbled because she was ogling the Yeshiva guys)
I will also say that there is a certain haskafah which tends to use the term “shomer negiah”, certainly when referred to as an optional practice akin to cholov yisroel. I have not heard that term used by bnei yeshiva or Beis Yaakov girls.