-Always good to double check and sorry for this wall of text:
It’s good in the sense that continuity is not overlapping (Composite Sync Yellow is not touching the White CSYNC/Resistor wire at all)
I also can confirm the CSYNC Scart Cable is wired from pin 20 to Din 7 with continuity. It is not wired to Composite Video Pin 3 Din.
However, only the CSYNC/Resistor/White wire will have continuity with the ground. The x2 pins the yellow wire is connected to doesn’t reach the ground, but that out put seems to be working just fine – see below
I found an old Sega Model 1 A/V -> Yellow and White RCA out… Plugged that in for kicks and it works! Mono sound and Composite video no problem.
This connector only uses the following pins = 1-5 (basically just the U shape)
So it’s Missing 6-8 (CSYNC, Blue and Red)
Not sure if any of that helps or we can safely assuming pins 1-5 of the DIN are okay.