Let me explain the allegory and how it relates to the problem.

We can directly observe some things, like the shift in frequency of light or the output of accounting software. We can make inferences from these observations, like our models of the universe or our belief that the software indicates that money has been stolen. We can also step into discussions about what our inferences imply, like the existence of something that would explain what our models tell us or the existence of a thief.

In the allegory, the necessity of a thief is contingent upon our inferences about missing money. In physics, the necessity of dark energy is contingent upon the validity of our models and the assumptions drawn from them.

The claim that dark energy has to exist is just too strong of a claim, as it rests only upon inference. Even when you make, as you do, the weakest possible version of the claim, which is to say that dark energy is whatever makes sense of our inferences, it is still too strong a claim, unless you include “our inferences have been incorrect” as a possible outcome to the question of “what is dark energy?”

If researchers wish to question some of our inferences and doubt some of our assumptions, it’s a good thing. Claiming that dark energy must exist whenever researchers question it is not helpful.

EDIT changed matter -> energy