I had this problem in January and through a slew of troubleshooting tips from Lucid got the car running again. Fortunately the car was in my garage at the time. Never did find a smoking gun, I just assumed a loose connection or something.

Today however, it would not start at work & is stranded there in the parking lot! I can't work on it till Friday but would really appreciate any suggestions.

The engine cranks with plenty of battery power to turn.
Spark on cylinder # 1 plug when cranking, though orange not blue.
Both Pumps run when jumpered (~5.6 Amp for main; 1.27 Amp for tank pump - low for an 88)
There was wet fuel at the return line by the pressure regulator after jumping the pumps, but not before (i.e. bone dry after multiple starting attempts)
I did not check for fuel flow to the rail.
Attempt to start with +12 V to Coil 15 & still No Start.
Tried to start with AMM disconnected & No Start.

There is a rattle in the exhaust which could be the CAT, would a plugged cat prevent starting?

Would a bad fuel filter reduce pressure to the degree that the car won't start?

Will a check for the fuel delivery (Bentley gives volumes for 30 sec of main pump running) confirm or exonerate the fuel filter?

Other troubleshooting suggestions?

Unfortunately this time I will likely have it towed to a shop if I cannot resolve the issue on Friday myself so any tips will be greatly appreciated.

Mike