Conversation so far:
Where did Hoyt Wilhelm play in his later years?
Hoyt Wilhelm played for the California Angels, Atlanta Braves, Chicago Cubs, Los Angeles Dodgers, and the Spokane Indians later in his career.
Did Hoyt Wilhelm still play baseball after his time with the Spokane Indians?
After his retirement as a player, Hoyt Wilhelm managed two minor league teams in the Atlanta Braves system for single seasons.
What teams did Hoyt Wilhelm manage?
Hoyt Wilhelm led the 1973 Greenwood Braves of Western Carolinas League to a 61–66 record, then had a 33–33 record with the 1975 Kingsport Braves.
What is the other team Hoyt Wilhelm worked with?
The Yankees gave Hoyt Wilhelm permission to work with Mickey Lolich in 1979 even though Lolich pitched for the San Diego Padres.
Did Hoyt Wilhelm ever become a coach?
After retiring as a player in 1972 Hoyt Wilhelm held longtime coaching jobs with the New York Yankees and Atlanta Braves.
Did Hoyt Wilhelm enjoying his job coaching?
Did Hoyt Wilhelm receive any recognition or awards?
Hoyt Wilhelm was inducted into Baseball Hall of Fame in 1985, after appearing in a World Series, being named to an All-Star team, and throwing a no-hitter.
Did any other interesting things happen in Hoyt Wilhelm's life?
Hoyt Wilhelm served in the United States Army during World War II. Wilhelm participated in the Battle of Bulge, where he was wounded, earning the Purple Heart for his actions.

Question: Why did they have to give him permission?
Self-contained rewrite: Why did they have to give Hoyt Whilhelm permission to coach?