I think at the time, people were speculating on what kind of movie Obi Wan would get, especially since this is during his sand hermit phase. So people were thinking maybe. he'd be this lone gunslinger (in between looking out for Luke and his fam). People were pumped since (General!) Hera was mentioned in one of movies so people were suggesting that Ben meet up with Ahsoka, and be like a Dynamic Duo dynamic. I think that's when some fans suggested Rosario and she responded quickly by saying that she's interested iirc