Wow this forum is dead.
Well,,, for me, you've just done such a thorough job of covering the the obvious problems that might be doing this to you. With all the stuff you've replaced nothing stands out as the next logical thing to look into. But, I'll dive in
to try to help.
Let's talk about your ForScan results. While Cranking
, what are the ICP (certainly not 2800) psi, IPR %, RPM, and Voltage?
There are No Codes? If you had connection issues between the IDM and the Injectors, there would
be codes (plus, this engine will start on 4clys, so it's more than a coupla injectors not firing). After doing your Buzz Test, do any new coders appear? (that's the way the IDM does a self-test of the entire system, during the buzz)
The wires you're Ohming out, they show a Higher Resistance than they should? (not Lower like a shorted/grounded wire would).
Anytime there are no codes and a serious problem, I first go to Fuel Delivery (no sensors to set a no fuel code). Think down that road. Verify again that you have a full bowl, good pressure, and that the fuel itself looks good.
Finally, since you've covered so much of the details, make sure your Engine Oil is good, Air Filter, and nobody stuck a Potato in your exhaust
I mean, it only takes Fuel - Air - Compression. What's missing???