John Staub, a concept artist who storyboarded ideas for the movie, posted the artwork for a deleted scene between Doctor Strange and Iron Man, which he describes as such.
In this version, Iron Man gets lost aboard the giant ship and is guided by the astral projection of Strange on his journey to finding the Doctor.
Perhaps it is because that scene exists that the filmmakers decided to remove the later scene between Strange and Stark aboard Maw’s ship.
We get to see some of this banter in the film itself when Doctor Strange brings Tony Stark to his home to explain the threat posed by Thanos.