I believe you mean that *Deception* was a reunion of the three "Now, Voyager" principals — not the other way around.

I did quite a bit of research on the Hays Code while I was working on my Ramon Novarro bio.
They helped to ruin at least one Novarro vehicle — "Laughing Boy" — and I'm sure that the 1935 musical "The Night Is Young" would have been much better had it been made two years earlier.

Now I'm curious to check out Bellamann's novel…

The making of King's Row, however, merits its own Wikipedia entry subsection.

Actually, Now, Voyager was a reunion for its three principals (you seem to have forgotten that Henrein played Davis's husband in Deception four years earlier).

As far as King's Row not going far enough, you should probably research the history of the Hays Code; considering the self-censorship guiding the hand of the film industry, it's a wonder that the film version ever got made at all, considering the themes that the screenwriters had to deal with — or, more inportantly, not deal with because of the Code.