The entirely natural origin of SARS-CoV-2 is as simple as CAGAC.
That palindrome, or its complement TGAGT, or the variant CAGAT, very frequently precedes a length polymorphism or copy-choice recombination event among Bat Coronaviruses.
Palindromes act like speed bumps for the RNA polymerase complex, rather like switches in a train yard. The polymerase can stutter or jump to another track, perhaps to jump back, or not.
Swapping out RNA sequences in bat caves is as simple as CAGAC. That in a nutshell is how this all happened.
I do believe you heard it here first.
Bill Gallaher