If I get to the point that I see two (or more) interpretations that both appear faithful to Ex 20:8-11; Ex 31:12-17; and Gen 1-2 in the matter at hand, I think this principle will make for a helpful guide. Until then, however, the problem is that I see no other faithful way to interpret those verses other than that “the Lord created for six days and then rested on the seventh.” There can be no reasonable dispute that this is what the three passages say; the only reasonable question is, “What does that mean?” Few people here have tried to say that it means something other than what it says; those who have, have not been persuasive.
As for the willingness to consider extrabiblical material, it was this willingness - specifically regarding the heavy weight of modern scientific testimony - that led me to BioLogos, and, in the most recent instance, consider what I labeled as the fifth stipulation for MC failure in the OP: namely, planned obsolescence of some or all of OT history. This contingency is easier for me to imagine than that someone will come up with a cogent interpretation of the three passages that blunts the prima facie meaning of the words.
I may need to re-think the term “obsolete” as, for me, it implies a spectrum from “fuhgetuhboutit” on the one end to significant revision on the other. That is, obsolescence does not necessarily mean that the OT history in view would be immediately considered faulty, but that 1) the parts that conflicted with SGH would be re-interpreted to fit SGH, and 2) the rest would be considered true but subject to revision at some point in the future should SGH eventually take positions in conflict with any of them. For example, we are seeing revised interpretations of the historicity of Adam and Eve in the wake of the Human Genome Project. This periodic revising of interpretation is the way things have generally been going in biblical interpretation in the scientific age. Stipulation #5 is an attempt to try to identify a scriptural warrant for this approach.