"the cam/crank sync comes & goes as you're cranking on live data but on the scope it doesn't drift "

where are you connected with the scope ??? at the sensor or at the computer ?

if the sensors are pull up design then you could have a good trace at the sensor and a bad one at the computer .

also , if your whole net work is down how can you talk to the modules ??

any chance its got petrol in it ? I know you said the injectors are not firing etc ,

But from what you have told us this thing should run..