Not that I know of; on the contrary, it's become the one source that every other book or comic about the Stargazer
has treated as gospel. Although it has been contradicted in a couple of small ways by later canon. For one thing, it shows Jack Crusher dying during a repair operation in space, but a later TNG episode established that Jack died on an "away mission," although no other details were given (so it's possible to reconcile it if you squint a little). For another, it was written based on the assumption of early TNG that holodecks were a fairly recent innovation, because there's a scene where Worf is showing off the Enterprise
's holodeck to the visiting Starfleet officers and explaining how it works, and they're all amazed as if they've never seen one before. It was later established that holodecks were an earlier and more commonplace invention, so that scene feels rather awkward today.
But those are no worse than the inconsistencies between earlier and later canon episodes when it comes to things like the holodeck or character backstories or whatever. For that reason, and because of how influential Reunion
has become on subsequent Trek Lit, I find it's best just to gloss over the minor continuity issues and accept the bulk of the work. (I just skip over the "Here's how a holodeck works" sequence.)