I think it is a level subtler than that. Value is downstream from utility - we consider something good because it is good for something. Most values are instrumental. Terminal values are a bit hanging in the air. The theist solution is to call terminal values simply instrumental values for god's purposes and call it a day. I.e. humans practically being gods property or tools. That way all values are instrumental, all goods are good for somethings and it is coherent.
The interesting part here is that if feels seductively intelligent. After all most people just consider those things values they feel remotely good about. To see most values as instrumental - for example, to see democracy as not simply something to cheer for, but a tool with advantages and disadvantages - is much more intelligent approach. To be able to tie down every value as instrumental, just some of them are not human instruments, feels super logical. It is a textbook case of "feeling rational" and this is part of why I used to be tempted towards theism in the past, as it makes everything make sense. "We have the UN in order to not have thermonuclear war! We want to avoid thermonuclear war so that we are not extinct! Why shouln't we be extinct? It would be the end of all problems and suffering... but maybe god has plans with us and he is our rightful owner! So let's support the UN!" You can see how elegant and tied-down it is.
The proper atheist solution is nowhere that elegant. I can only argue from a Heideggerian "we are thrown in the world and must cope". We are the accidents of evolution thrown in a world that is an accident of the big bang or quantum many-worlds. We cope however we can. Part of that coping is calling those values that are most likely to make life bearable for most terminal values. It is not elegant at all, and I can understand why it is less attractive than theism. But it is more probably true.
It's only coherent if you don't expect it to solve the problem (rather than hide it from your view). It's only attractive if you expect God to fulfill your own terminal values. You should be able to see contrary hypotheses, since you say one of them is close to being true (or at least more likely).
ETA: Actually, the view discussed in the parent could probably be made coherent, but not sound for the true natural numbers, at least not without straightforwardly defining the word "morality" to mean something else which I don't care about. You could i...
Link to Blog Post: "Extremism in Thought Experiments is No Vice"
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