Changhuxinyimen - Li Jiyu - found our guy?
Looking at some dates, Chen Wangting (1580–1660) and Ji Longfeng (1588-1662) were contemporaries. Which puts Li Jiyu and Ji Longfeng at about the same time as well. Li Jiyu may have been a Mogou practitioner who became a student of Ji Longfeng.
We've known that the Xinyi (and Xinyiba) related material in Shaolin, as well as the development of Xingyiquan, came out of interactions with Ji Longfeng and his 'rooster style'.
It then stands to reason that if Changhuxinyimen was the name of Li Jiyu's sect and its representative boxing set, and his old sanctuary was in Mogou village, then he is the man who mixed Mogou Xiaohongquan with Ji Longfeng's Xinyi rooster style, hence the current name and style.
That would definitely explain things like Mogou XHQ and original Qixingquan that is more like traditional Shaolin being altered into their more 'rooster style'.
That would also explain why the current patterns are so identical between CHXYMQ and Mogou XHQ, because it was not that long ago that this took place. Just over 360 years or so.
It is strange though that the gongfu of a sect that killed the monks would become one of their most popular styles in and around Shaolin, but then again maybe not? It must be pretty lihai.