Why not just take Grogu to Luke?
Luke Skywalker, hero of the Battle of Yavin and the destruction of the first Death Star, and likely well known regarding the Battle of Endor which ended the Empire, should be well known throughout the galaxy either way, is training Jedi at this point, and is linked to the New Republic leadership.
It is only 5 years since the Battle of Endor and the destruction of Death Star II and the end of Emperor Palpatine and Darth Vader.
Why wouldn't Ahsoka Tano mention Luke to Mando at all? She would have been so dazzled to find another member of Yoda's species alive, that she probably would have gone with Mando and Grogu to see Luke Skywalker.
My goodness, Luke is a Jedi Master, trained by Yoda and Obi-Wan Kenobi, he would be the person to see regarding Grogu.