When you know that the due process (which involves making sure he doesn't have the ability to later claim that due process wasn't followed) requires an in-person interview, then throwing up platitudes (that you know won't, can't be accepted, but which make you look entirely reasonable) is duplicitous at best.

Point me to any country in the world where a telephone interview of a suspect or person of interest in a crime is an acceptable totality of due process or investigation.