Regarding the flash sync assembly, that was one of my suspects. The other one is bent shutter trigger assembly.
The shutter does work in some sense. If I do the following, I can trigger the shutter mostly:
1) Pull up the shutter release (which also closes the 2-blade rear shutter)
2) Tension the shutter
3) Push down the shutter release (which also opens the 2-blade rear shutter)
4) Gently push back the shutter tension lever. And the main 5-blade shutter will trigger. And most speeds sound ok, except maybe 1s and 1/2s. B also works fine.
Two other things of note:
- The shutter release cable socket does not work either.
- The shutter release does not return automatically, so maybe there is a spring missing as well.