You were wrong then. There's no chance that the boy should be named after Pearl Version, because the main heroes in every manga have never been named after the secondary game, always the first game. And their rivals, of course, were named after the secondary games, such as Blue, Silver, Sapphire, etc, etc......
But I was kinda hoping that the girl's name would be Pearl, cause it fits her! That's right, it fits her completely! But it's still okay, my thought that only the girl should choose the water penguin turned out to be correct. She would look horrible with Hikozaru, although Hikozaru is a pretty good Pokemon. It does not fit a pretty girl like her, however. The pretty girl always chooses the cutest Pokemon. And it should always stay like that.
And, yes, the girl's actual name is Hikari. It's not Pearl or anything else. Like, the girl in RSE is not called Sapphire in the games, she is called May. Although we're talking about the manga, I don't think it's wrong or stupid to go by calling her Hikari. And the stuff about her family name being Berlitz is completely false.