I think “Jedi” does imply that Luke’s return to Dagobah in the film was his first since he left for Cloud City, when he says to Artoo “I have a promise to keep to an old friend.” But, it does leave the option open that he may have been back before. It would certainly make more sense, since the entire time he spent on Dagobah in “Empire” - if we’re comparing it to Han & Leia’s experiences in the asteroid field and in Cloud City - fell somewhere between a couple days and a few weeks. That’s not much time for Luke to “already know you, that which you need.”