No, this is not authentic. One should offer salutation to the Prophet salla Allahu alaihi wa sallam as he taught us and not only when in the Rowdah.

Sheikh all he people at Al Rouwdah recites “Assalamu Alaykum Ya Rasoolallah”, “Assalamu Alaykum Ya Nabi Allah”, “Assalamu Alaykum Ya Habeeb Alla”. Is this reccomended, is this authentic or is this preferable