Eh, I think there's an implication that Blake recognizes her as well; they know the guy's a slaver, Artemis is obviously a slave, there's really no reason for him to wonder if there's anything to her past that unless she strikes him as someone he should recognize. Plus he asks Scandal and Jeanette specifically - "ether of you" - rather than posing the question to the Six at large, which suggests he's looking for confirmation (since as you say, knowing that kind of thing is what Scandal is for) rather than general information (which anyone might have).
Either way, for Jeanette to recognize her is still fairly significant IMO. "Wonder Woman" was portrayed as a very low-profile, lower-tier name in the WML years, and Artemis only held that title for about five minutes, during which she accomplished exactly nothing, saved no days, and rescued no kittens from no trees - not to mention that Diana was still operating in the high-profile JLA chair position and the rest of the cape community treated her like nothing was different, so to most of the world it would have looked more like a standard heroine costume change than "hey this Artemis dame is important" in any way. By the Jimenez era she'd become half the government of Themyscira, but I could certainly not pick out of a lineup the political leaders of countries far more active in Western affairs than the amazons ever were. So she's certainly not famous enough to recognize like this on her own merit.
Which means that if people know who she is, "Wonder Woman" and the people and culture orbiting that title are a far bigger deal in the DCU than previously advertised. Which, y'know. I can't say that bothers me.