For anybody else wondering about this, the path can be derived in OliveTin, using:
Search the last 100000 lines for [SYS] Starting Channels:
And:
The path you want for LOGS_SHARE is everything up to, but not including /data, in the path shown. This is for people where OliveTin and Channels DVR are on the same system.
For those where they are separate, this is the path you want share on your LAN. Then you'd use the Docker-Volumes approach to connecting via Samba or NFS.