It is of course impossible to verify either way, but I am very sure these statistics of 96% savings in freshwater are total nonsense. Anyone who has ever cultured cells on any scale can attest to the amount of water needed at any scale in terms of washing, rinsing, diluting, sterilizing, feeding, etc. Moreover, we have seen time and time again, the reporting of extremely high numbers for water usage in beef and milk production, but it turns out they are counting the water that falls as rain on the pasture land, or the rain/ground water used to grow the alfalfa. Should that be counted? Rain seems to be fairly renewable, but I admit that (in the extreme) society can harm ecosystems by diverting too much rain water (see Colorado River). Ground water renewability is a bit context dependent.
If the water savings is mostly nonsense, well then I also question the savings in GHG emissions. Land savings? Sure, fine, that makes sense... but farm land is orders of magnitude cheaper than land that has a fully functioning cell culture factory on it.
In the end, we will know if this works by what price it can sell at and make a marginal return. The jury is out on that one.