James had been working in a top creative capacity on the SmackDown brand for several years, before stepping down from his position shortly after WrestleMania 35 last month.
The former multi-time WWE World Tag Team champion was said to have become "increasingly frustrated" with Vince McMahon's alterations to his scripts, and the SmackDown in Brooklyn following WrestleMania proved to be the end of the line.
After resigning from the lead writer position, James remained on board as a "utility player" of sorts, before a regular position for him was found.
By joining NXT, Road Dogg reunites with some of his old DX comrades. Triple H is, of course, the brand's founder and head shot-caller, while Shawn Michaels is employed as both a producer and one of the Performance Center's ace trainers. Former New Age Outlaws partner Billy Gunn, meanwhile, is a producer for All Elite Wrestling.