Update to the problem with exporting: I saw here @jethro’s use of org-id-extra-files in his export process:
(let ((org-id-extra-files (find-lisp-find-files org-roam-directory "\.org$")))
(org-hugo-export-wim-to-md))
I’ve tried this and it is working for me also when exporting via org-publish, e.g. with similar to the below in my publish.el:
(require 'find-lisp)
; ...
(setq org-id-extra-files (find-lisp-find-files org-roam-directory "\.org$"))
From the definition of org-id-extra-files: “Files to be searched for IDs, besides the agenda files”.