Why The Pseudonym?
"Moses Avalon" is a trade name. This name was selected to protect the privacy of those who are discussed in the books authored by Mr. Avalon and to protect the sources that supply the company with inside information on the music business.
The actual work of The Moses Avalon Company is not the result of one person but a group of anonymous advisors whose contributions are edited by the company's trustees. While it might be fun to explore the actual identity of Moses Avalon, and it is certainly within your rights to do so, posting or publishing any information could involve privacy issues.