I do not know this machine, but was just working on an earlier Gottlieb and the D relay was in the backbox. I assume other machines have their D relay too close to the score reels, but could be wrong. If it was completely missing, that would be a pain, but I assume it has a switch that triggers the bank reset and so that seems extra odd if the bank reset coil engages when the reels are resetting. What does the lower part of the schematic show with regards to the switches in the bank reset coil circuit?
And if you do find the D relay, it’s possible that at least one of the score runout switches on one of the score reels isn’t closing or is dirty and this is what is causing the bank to reset without completely resetting the score reels (if I understand the problem correctly). In other words, the D relay is disengaging too early. If you do have a D relay, look at what it’s doing while the score reels are beginning to reset.