If I remember correctly, either Christopher or David Mack at some point mentioned that several plot points in the novels were ultimately contradicted by Into Darkness. It's possible they just read the summaries and cancelled them for that reason.
No, that was certainly not the reason. If that had been the case, they would've just asked us to revise the novels, as happened many, many times with novels that came out while TNG/DS9/VGR/ENT were on the air. And there's no reason it would've led to a change in the status of the whole license. The cancellation was a business decision. It wasn't about anything within the books themselves.
As for the incompatibilities between my
Seek a Newer World and STID, it's not so much contradiction as redundancy -- they both covered some of the same conceptual and thematic ground in terms of character arcs and the aftereffects of Nero's attack on Starfleet's attitudes. That's certainly not a reason for the cancellation, though; it just means that if my book had been published, it wouldn't have held up that well in retrospect.
As for Gorn. Why should they lay eggs? Because they look like Terran reptiles? They're aliens.They don't have to follow Terran norms..
But they're shown as egg-layers in the graphic novel
The Gorn Crisis, which is included as part of the novel continuity. And apparently in
Seize the Fire as well. The issue being raised is that STID seemed to contradict the novels on that point. (Although I disagree, because
Seize the Fire also establishes that the Gorn have engineered themselves into various different subspecies, so it's possible that one of them could give live birth.)