Why are interviews not included in the references?
Personal interviews/communication whether it is conducted in-person, phone, email, virtual (i.e. Skype, WebEx, Google Hangouts...) are not "recoverable" data and therefore a reader would not be able to go back to the source to review the interview.
NOTE: If you recorded the interview or Skype meeting and posted it online (i.e. YouTube, web site) you can then include the reference and direct the reader to the audio or video file that captured the interview.
See: APA Blog - How do you cite an interview?
Important Note: Personal interviews are not included in the reference list because they do not provide recoverable data. Cite them IN TEXT ONLY.
Personal Communication Includes letters, phone calls, email messages, and interviews. (p. 179 section 6.20)