There are two things I'd suggest to check.

I didn't catch if it hits and fails to start.

One is the ballast resistor. Look for corroded connections on it which might stop a good spark in the run position. I think I remember finding it in the hole under the a shock tower. I said "a" because i don't know which?

Second thing is just when you stop cranking, do you hear the frequency valve buzz and the pumps shut down?

This confirms that a little sliver relay on the battery side fender is working. Its about an inch square. This is turned on by the injection system side of the fuel pump relay.

The relay allows the 0-2 sensor circuit to work.
There is a separate circuit for the frequency valve. If the frequency valve fails to buzz the mixture may be to rich. This creates some very hard to start moments.

It would do this randomly to me. Took a long frustrating time for me to find it.

Its a two pole single throw relay. It was hard to locate at parts store. Too expensive for what should be a common relay. I shined that on and found one on a '86 model at Pick&Pull. Its down by the foot pedals. I don't know its function on the car but it has the same symbols.
After clearing that problem the car has been flawless in starting ever since.

Anyway, I feel your pain, its just some thoughts for you to rule out.

Phil