From my reading of Middle Eastern culture, followed by Native Americans, too. Naming gives you power over the named. Attributes are typically chosen. I AM What I AM is a refusal to be named and, therefore, limited, in any manner.
There is no saying of Jesus in canonical or other lit. authorizing JWs. The early Christians of many denominations have that claim. The Roman Catholic Church, Protestant tho I remain, has a historical claim. Jesus did not found a religion. Paul did. And Paul had many opponents.
Altho I was born-in, I find this very embarassing that I ever gave JW legitimacy. Charles Manson had as much. The schizoprhenia on an urban corner had as much credence.