That is not correct, the FDA have not asked for a new, a better,...

That is not correct, the FDA have not asked for a new, a better, or a validated assay.

From the exact same conference call, that I also now can't belive both you and JB 1975 have not heard or chose to ignore,

" The reason for the CRL the FDA remains..... wanting to be convinced that product in the inventory for commercial launch is substantially the same as that used for the phase 3 trial, and our potency assay needs to be substantially the same potency assay as that used in the trial to demonstrate that the two products are the same. We have those data that are being developed. Some are in place, some need to be added, which will be over the next few months.

As clear as you can possibly get. The issue surrounding the potency assay is not a lack of validation, it is the assay data from the commercial product lacking something.

If the FDA are not happy with the potency assay... as the FDA said in their own words, they will not allow MSB to conduct the adult trial.
If the adult trial starts, the FDA are happy with the potency assay.