I think it's worth noting that that document links to the Github for the sync server, and that page says "Note that this repository is no longer being maintaine

I think it's worth noting that that document links to the Github for the sync server, and that page says "Note that this repository is no longer being maintained. Use this at your own risk, and with the understanding that it is not being maintained, work is being done on its replacement, and that no support or assistance will be offered." So yes, you can probably get it running in docker, but bugs etc won't be fixed unless you're comfortable working on older Python code.