Who can shoot the tech's?

[tnroundballref]

I worked a Beast of the East tourney in DC this weekend and ran into a request from a coach that I had never heard of.Team B player is stuck with a "T" because he wanted to officiate more than he wanted to play. Team A's coach wanted a kid that was on the floor to shoot the 1st free throw and said that if he missed he wanted to sub a kid in from the bench to shoot the 2nd shot. This was a new one on me. I told the coach that I didn't think 2 players could shoot the free throws. He said he was sure that they could. I told him that he may be right but I only let one kid shoot both free throws (he made both). After I got back to the hotel, I looked up the ruling and the book stated that the coach or captain can choose the thrower(s). The (s) led me to believe that the coach was right. Thoughts from the gallery?