Justine is the only wrestler who is horrified by Sam's dating profile. We later learn that he's her biological father, so of course she'd be creeped out by watching him talk about his cock.
When Ruth presents her stereotypical Jewish character, Melrose immediately responds with an angry, "What the fuck is this?" An earlier throwaway line, in which she calls Cherry an antisemite, established her as Jewish.
Melrose is the one who notes that Beirut is a city and Hezbollah is an organization. Israel was involved in the Lebanese Civil War at the time, so a Jew like Melrose would be paying more attention to the issue than the other wrestlers.
In the end, the only one who doesn't wrestle in the pilot is Justine. Her in-universe reasoning is that she came here for Sam, not the wrestling, but her age is also left ambiguous and it's possible she's worried about a lawsuit if she wrestles before she's 18
