Well for starters there is a picture of her at a scientology gala in 2013. And she most probably still is, because it's incredibly hard to leave scientology. They put an unbearable amount of pressure on you to stay/come back, and if they determine you're a lost cause, you become a "suppressive person". When that happens, all scientologists are forbidden from any kind of contact with the person. So for her, leaving scientology means losing her family, her closest friends she'd known since forever, and any kind of support structure.

Dead Sara's drummer was also born into scientology. Chances that they both left are very slim. Chances that a scientologist would play in a band with a suppressive person are nil.

Chances that she left scientology, then decided in 2020 to come support scientologist Masterson, who would have been absolutely forbidden from interacting with her in any way, and with a group of scientologists also present: also nil.