Participant; it probably is correct, but it doesn’t change the cultural association
Health; slang has use and is defined by its common usage. I’ve never heard Harry used to describe a litvak, OTD or MO person. I’ve only heard it used to describe people who are shomer torah umitzvos fully, but dress more American, don’t use yeshivish lingo, go by English names(that’s a given), and are otherwise removed culturally(but not religiously) from the Yeshiva world