I had a similar problem some times in the past with an old 1.5 engine I had in my Sprint.
That engine refused to start if the battery wasnt completely full ! It also had the 4-3 cylinder issue like yours, but mine was a mess.
The electrics on that car were shot, I had to replace a ignition switch as the pin which connected the 12v to the engine via the switch was corroded and it either gave out less than 10volt or none.
Then the coil was full of water ... I have no idea how that happened
And finally the fault on the firing was due to , would you believe it , MISSING 2 valve seals on one of the heads !
I patched that engine up and I used it on my black 33 until recently. Never actually worked the way it should, but it did the job
If you have black oily wet sparks, then you are probably dripping oil from a cracked valve seal over your sparks. A good way to test it is take out your sparks, clean them up or put clean ones in - as it could as well be a faulty spark - and give it a turn with a full battery.
If its not electrical, it should start