I wonder if Rabi Banaa entered the place where Adam HaRishon was buried or not. Strictly the Bat Kol did not permit it and when he claimed that he need to measure the place he was answered that there is no need to.
But from the rest of the story we learn that he did enter the place as he knew how Adam and Even looked like.
Thanks in advance.
The source for the statements in the Gemara comparing the looks of Adam and Chava to others was not necessarily Rebbi Bena'ah. They seem to have been Mesorahs, not directly related to the adventure of Rebbi Bena'ah. (They allude to unique qualities that Adam and Chava possessed, see Insights.)
The Gemara does say that Rebbi Bena'ah saw the heel of Adam, and Rav Yakov Emden (in Hagahos printed in the Neharde'a Shas) asks, as you wrote, that this contradicts the previous statement of the Gemara. He answers that Rebbi Bena'ah didn't mean that he literally "saw" the heel of Adam, but that he contemplated the quality of Adam which is alluded to by his heel. (He proposes a very interesting allegorical meaning for the entire discussion here.)
The simple reading of the Gemara is that he was not given permission to enter and see the face of Adam. From outside the grave, though, he was able to see his heel, which was positioned near the entrance to the grave.