The work outlined in the actual paper is quite remarkable. Within this 6 month period they generated transgenic mice with the precise mutations (paternal and maternal) this baby had in order to test treatment for functionality and toxicity as well as a doing a toxicity study in monkeys.
To those thinking about commercialization opportunities, these two steps seem the most labor intensive and time consuming, but also the most necessary in order to actually have confidence to inject completely customized gene editing therapy in a kid.
(Also worth highlighting for folks opposed to animal research.)