The fact that Regavim is not a settlement but is a NGO is not a matter here.
The reasons to give both the pov of the International Law and Israel is to comply with NPoV and the wording that are used were based on discussions to avoid edit wars on the topic.
It is relevant here given Regavim (NGO) defends the point of view of the settlers and emphasize the legal aspects.
That's totally obivous. I add that you asked for a source that was talking about Regavim in this context and you was provided by me here above. I will not write this a 3rd time.