Probably a bit late but this did happen to me and my ex-girlfriend. We both got scouted separately. Just for the record I'm Indo citizen of Arab descent, and she of Anglo-Celtic Australian descent. We were both scouted in and around Central Java.

I got scouted at my school's reunion party of all things. Someone who claimed as an agent approached me, handed me their card with their contacts and socials, and told me there's an upcoming casting event that I might be interested in. Cursory browsing on their socials seemed to confirm him as legit. On his insta page there are names that my then girlfriend recognised: an Arab-descent sinetron actor, Arab-descent who's modelled for a coffee ad campaign, and a Pakistani-descent sinetron actress who recently got embroiled in high end prostitution case. My initial reaction was just like yours, skeptical. Especially the agent was being somewhat pushy about it. That's probably what you should be looking for first. Most agencies even in Indonesia, have this sort of catalogue in the form of either a website, or an instagram page at the most basic. I didn't end up taking up that offer since I'm just not interested in showbiz industry.

The way my ex was scouted, I think qualifies as stalking hahahaha. She went to normal state school in the past and I think the agent just worked their way to her through her friends and acquaintances, and maybe asked around if they knew anyone who looked bule-ish in their year. She did eventually scored a gig at I think a resort hotel in Yogyakarta as a model for their promotional contents, but I don't think she's had any more involvement in modelling after that.

Honestly the money really isn't as good as the agents make it out to be. There seems to be a trend of moving away from bule-ish looking models and more representations of the classic Indonesian look. There are just now a lot more mixed race Indonesians than before and it takes a lot more than just 'hidung mancung' and 'badan tinggi' to stand out.