The bigger problem for them is that the evidence is squarely against a single couple genetic origin of Homo sapiens (though maybe a single couple origin with interbreeding might work?). If I could imagine a way to make it work, I would. However, I can’t imagine how the genetic data can be squared with their model. They do not have to like a genealogical Adam, but there current model is broken.
If they move to an @Agauger or @vjtorley model with a single couple origin much earlier, that creates special problems for them. Given their past positions, they have to accept evolution with in the “humankind”, after Adam, because we see (according to them) clear distinctions between Neanderthals and Sapiens. This puts them in a very uncomfortable bind. They have some work to do, but the TMR4A case I laid out is easy to understand, and does not rely on questionable assumptions: Heliocentric Certainty Against a Bottleneck of Two? - #12 by swamidass.
Very curious to see how things pan out.