Another of the new casebook plays

[Scrapper1]

Case 3.3.5 Situation B. Without typing the whole thing out, the free throw shooter's shirt is untucked. He's instructed to tuck it in, he shoots the free throws with no one on the lane, and is required to leave the game after the final free throw. The ruling says that Team B is awarded the ball for the ensuing throw-in, regardless of whether the final free throw is successful.

Does this seem right? Seems to me that if the final free throw misses, we should go to the arrow. Anybody see a rationale for automatically giving the ball to B?