Interesting contribution. But, I really think Boeing has very little to do with the design of the reverser system. Has much more to do with the designer, manufacture of the engine. The aircraft designer may make some preliminary input, but it is the GE, Pratt etc.. that put it all together.
The reverser is part of the aircraft powerplant pod and not the engine. As such it is designed and certified under the aircraft regulations, not the engine regs. It can be manufacturerd by any supplier under the oversight of the aircraft certifier as part of the installation.
Tis true that engine makers are happy to manufacture and sell them as middlemen themselves.