Hi Renaat,
I don't know the nature of the incompatibility that you are talking about, actually, I would really like to talk to you about the problem itself.
Going back to the question that you have originally asked, I think there may be some misunderstanding of what Moodle Workplace product is. It is not a fork or something completely different from Moodle LMS. It just adds functionality ON TOP OF moodle.
In the majority of cases, Moodle LMS plugins do not need to have any modifications to be compatible with Workplace. They may not FULLY work with multi-tenancy, but it's not a bug, it can be considered a feature request and we definitely would encourage premium partners who are interested in such feature to fund developer's work.
Here is an article in our documentation about plugins compatibility with Moodle Workplace https://docs.moodle.org/en/Workplace_plugins
In my opinion, there should not be any need for plugins to specifically claim that they can not work with Workplace because in the majority of cases it would mean that they can not fully work with the granular permission system in Moodle (i.e. they use course-level capability to access users or other system-level entities, or do not respect course listing visibility).
Again, if you want to talk to me about the problem that was reported to you, I'm here.
Regards
Marina Glancy