If any of this is true, and I don't have enough brain power to decipher if it is or is not, would it be at least in the realm of possibility that Omicron was not an accidental leak; perhaps, rather, a deliberate one, to counteract the original (and Delta variant's) virulence and impact?

We know that the virus is likely to continue to mutate in the wild, on its own - and that the virus in the wild has upended our way of life with great economic costs. Is this a viable path way to introduce widespread natural immunity? Omicron introduces mutations with extremely high contagious properties but very mild virulence. In one swoop, you expose vaccine-hesitant and developing nations to a virus they're likely to survive, help inoculate them against future mutations and outcompete the dominate strains such that the human race is somewhat protected against future infections.

In effect, you kind of "undo" the original mistake.