The real truth is that George killed Obi-wan as a plot device rather than keep him alive as he had nothing to do in the third act of Star Wars.
But he managed to put Obi-wan in the cockpit with Luke so it was not a bad decision really. As the Saga progressed it got more messy.
But it created a nice mythology. Sorry about that…
That begs an interesting question, did they shoot Luke’s scenes in the X-Wing before or after they made the decision to kill off Obi Wan? Could they have shot any scenes with Ben post Death Star?
Well Wedge was played by a different actor and then Wedge became Dennis Lawson so it’s possible Ben was milling about on Yavin IV at one point?
It obviously got quite a radically restructured ending.
I wonder if Ben Greeted Gold Leader as they would have known each other because Ben knew Luke’s father and so did Gold Leader.
Nobody for an instant morns the Loss of Obi-wan Kenobi either so I’d say yeah he had scenes on Yavin.