Where's Skif?

I realized tonight that part of Mercedes Lackey's popularity is her ability (and by "ability", I here mean "inability to do otherwise") to make the protagonist of any given book the most important person in the universe. This is a bit surreal, though, when the characters surrounding the protagonist were main characters in their own books, once upon a time. So in the scene I was reading tonight, our protagonist Elspeth* rides with a whole big group of people into the palace, and they're all formally received by the Queen. So Talia (another heroine from a different book) came running out to greet Elspeth, and they all go in - except that somewhere in the last dozen pages, Lackey misplaces Skif. Who, yes, was also the star of a book, and who is one of Talia's best friends and Elspeth's official traveling companion. His girlfriend is there, various bit players appear - but this fairly major character has just disappeared. Talia doesn't greet him, he's not with the other Heralds, he's not anywhere.
Does this matter to the plot? No, but it's a fairly noticeable mistake, and lately I've been all about making fun of Lackey.
* I'm amused, by the way, at how Lackey's characters have obscure (Talia, Elspeth, Alberich) or misspelled (Jeri, Myste, Keren) names from 20th-century USA. At least when Marion Zimmer Bradley gave all of her characters Celtic names, she explained it by saying they'd come from Europe originally.