Very possible is a stretch, at least for rounding out the Retro line. If there were any hope to get the Retro figures out, NECA would have just delayed the release of Brody. They were already taking orders with vendors and such, they would not put themselves in a position to tell collectors sorry to get your hopes up for nothing, unless that was the very last option available to them.
Is there a possibility for the more realistic style, traditional action figures from them, yes, I don't think it's a high possibility, but, if the issue came down to how the Retro figures look compared to what a traditional NECA figure would look like, then of course the solution is simple, but who knows how much, if any, work NECA has put into doing those types of figures of the guys to appease that, or if they'd even want to. Retro figures are much easier to produce. The costumes are simple, the bodies are re-used, much less tooling and molding which is probably why they went for Retro in the first place. I believe that Retro is the choice of figure style for things they feel would not sell well enough to justify the costs of traditional figures.