There is a remarkably easy way to link to the UUID of sources/documents in DEVONthink.
In DT: index your obsidian vault, open the target note, then select the sources/docs you want to link to and Cmd-Alt-Drag & drop them into the note.
Presto! the link(s) show up, properly formatted and named in Obsidian.
(It took me a while to find an answer to this – and it is useful for DT users --, so I’ve crossposted this answer in a couple places here and on the discord server).