I expect that Athearn and/or MTH will get to doing the SD70ACe heritage units, some time after those appear. As for the ES44AC units...
Intermountain is currently producing both ES44AC and DC units, but they are the first production ("Phase 1" if you will) of the GEVO line. The NS ES40DC they produced is accurate for the early NS DC orders, but neither it nor the ES44ACs they have would be accurate for the current GEVOs that NS is painting up.
To do the heritage units properly, they would need to tool a new long hood with modified radiator section and rear (new high horizontal headlight, etc.), as well as the new cab style (with four-piece side windows, nose-door on the opposite side, and the notch cut out where the nose headlight would otherwise be) and the new thicker stanchions.
IMRC may very well be planning to do the new style GEVO eventually, although there were a few distinctive iterations in between that they might also want to tackle. I suspect though that it would be in their best interests to do so. With GE continuously attempting to standardize GEVO features, we are now to the point where new GEVOs built for the different Class Is are virtually identical (short of the paint scheme). A CN unit, for example, that once had tear-drop windshields, a different anticlimber, and nose-mounted marker lights, is now indistinguishable from a new CP, UP, CSX, or BNSF GEVO. Heck, even the rear ditch lights that were once unique to CN and NS are now standard. The NS still gets to be unique with the cab headlights.
So if IM tools the newest phase, they can do one loco with minimal variation and put every paint scheme on it accurately. If they do, they can also do all of the NS heritage units.
Athearn has also apparently said they are still working hard on bringing out their GEVO, although I ave heard some mention that they are doing new tooling instead of just working with the T55. So perhaps Athearn will make the latest variant, since it is more uniform across roads and IM has already covered the first phase. In that case, Athearn could do the NS heritage. Otherwise, they could not (without it being a foobie).
So in essence, while the SD70ACe heritage units could be done (when the prototypes are released) by either Athearn or MTH realistically soon, the GEVO units cannot accurately be done unless (or until) either Intermountain, Athearn, or another manufacturer does a proper current production GEVO. IM's current offering simply can't cut it.