When the Forresters arrive, he mentions something about a cat ("You brought the dog. I don't want to hear any more about the cat."). He then pretends to "fish" Russ Thompson, Sr. down from the foundation and they give each other high fives. When he and Russ talk, Don doesn't seem interested in what Gloria witnessed: Wayne flying. He is dismayed when Russ says that plumbing was keeping the Thompsons from going on their fishing/camping trip despite a non-refundable $80 deposit, but they part.
Eventually, however, when leaving, Don strangely does see Wayne flying.