Some thoughts are appropriate here:
It was known that real Rodinal did not require a filtration step to prepare. This is one of my balking points with some of the formulas. It was made in-situ with no filtration. If you didn't know this fact, sorry to spring it now. In addition, there was a final ingredient added just as the material was packed into the bottles for shipping. Sorry again if you did not know that!
Going back to the formulas posted on the other thread, they seem to be quite alkaline, as much as 11.x and these current formulas seem to be more neutral. So, I ask, which is correct. This is more or less rhetorical as it won't help much except to know the "correct" pH, not what got us there.
And, use or even the exact amount of Metabisulfite used will tell us nothing about the final product as the M will rapidly decompose into Sulfite, Bisulfite and a mix of Sulfates in addition to any reaction with the p-Amino phenol.