I think you have made too many assumptions with your wiring. Has the ecu got the required power supplies and earths connected?
Pull the plug out of the ecu and assuming that the pinout diagrams ( they all say the same thing) are correct, test every wire to see if it is going where you think it is and where it ultimately goes to.
Have you got fuel at the injectors? If you turn the CAS by hand can you hear the injectors? Are the plugs sparking?
Have a read through this (there is some useful info half way through)
https://www.gtrusablog.com/2016/07/nissan-skyline-gt-r-ignition-coils.html