No competent implementor of high safety software will create the software in which critical data is co-located in the manner described. This kind of design would be explicitly illegal and that set of rules would be strictly enforced, usually both by manual independent review of the software and by automated software analysis.
FERGUSD...concur 10000% (did not include your entire post in quote,but yes)
Redundancy is there for a reason...the complex algorithm to combine resources...and determine the correct solution....lemming talk. (statically indeterminate)
Hopefully, that Boeing provided that info in a press release, well, perhaps blame the messenger, BUT if this is really the path...damn.