No, synced is a timing thing. All GOUT-synced audio will work with any GOUT-synced video, so people’s lips match up with the words coming out of their mouths, etc. Silver Screen isn’t GOUT-synced, so you are a little more limited in your audio options (or you add dark frames for the missing video to make it GOUT-synced, either way).

They don’t sync because projection prints are often missing a frame or two at the ends of reels. Also the GOUT may very well have included more frames than any theatrical print would have included. Either way, the audio for one won’t line up with the video from the other.

All of Harmy’s versions are GOUT-synced, so you’ve got the widest range of audio options. Film scan-based preservations can’t really be GOUT-synced unless you add the extra frames from another source (or blank frames) at the reel ends. There are lots and lots of GOUT-synced audio tracks, not just the tracks from the GOUT.