Do you have some sauce to go with that platter? I work commercial aircraft, and while they have fancy gadgets, external cameras are limited in deployment because of cert and maint costs. I have yet to encounter a single camera for the years I have been working.
That is more inline with what I know. IFE is bad enough without coupling video feeds from onboard cameras. The engine caneras should be for pilot use for condition check. Only airframes I know that offer from factory are the a380, a350, and maybe the b787, though I haven't been hands on with that one.