There is a lot of confusion in spirituality. Partly because of Sanskrit language and the same word having multiple meanings
I suspect god wanted it this way , so that a disciple realizes he has to go to a guru for further progress.
Take the word kriya yoga ! So many people have taken it in a million different ways!
Some look at it as a type of pranayama : with five levels
Other look at it as awakening if kundalini and spontaneous action
Some look at it as a form of action
Then some people make impressive drawings and draw chakras and give a very lucrative descriptions
All is wrong but that is all people will grasp. Since what was meant by Babaji has been lost. Yogananda write it clearly in god talks with Arjuna
Sad. But good luck in your search
Bhavin