Oh no, Laenor is 100% killed in the book, in a public place with numerous witnesses no less.I don't think he absolutely dies in the book, by the way the book is written a successful fake death would just show up as a weird, conveniently times death.
My bet is that Laenor will take over as another character and if he is alive it makes complete sense that they wouldn't just ignore the fact they have a dragon rider on their side. It's going to be cheesy but the official story that is told when this other character shows up out of nowhere is also not believed in the book. What I didn't like is that the show left Corlys out of this plot apparently and that sucks.
I'll try to be vague about this and can elaborate in the full spoiler thread if anyone asks, but Laenor being alive
might let him come back to stand in for characters initially thought to be his bastards [but are more likely his dad Corly's bastards]