They are using synthetic psilocybin. It would be impossible to make a translation between grams of dried vs. synthetic. Different species have diff content, liberty cap vs. penis envy etc. also stalks vs. caps typically differ in str.
Dosage guides for dried shrooms are already universal in recommendation of dosage typically speaking in terms of grams without bringing up the individual strain. This leads me to believe that a generally close conversion should be reasonable from the dried natural to that MG number.
It's more like the measurement is off so much the differences don't even matter.