THE DESTINATION:

"recovering our unity within the divine, union with God, realization that you are not different than the naturing of mind, etc."

Krishna Prem, in his commentary on The Yoga of the Bhagavad Gita, speaks of one universal path (citing the Vedic "Paths are many, Truth is one" - meaning, to be clearer, though paths APPEAR to be many, there can only possibly be "one" path - but it is the "one" you refer to as the seemingly infinite number of ways to get from Long Island to NY City!)

I could even parse it more. I lived on 9th street and 2nd avenue for 25 years (East Village, Manhattan) on the 6th floor. If I walked down all those flights of stairs, I never walked the same way twice. Even if I walked up and down 25 times a day, every day for 25 years, each of those thousands of times would be different, but the starting point and end point is the same, so you could say, paths are many but paths are One.

But when it comes to an infinite realization, there may be other ways to talk about the "end point."

Your choice of the oxherding pictures is particularly relevant, since picture #8 was conceived of as the end point for quite a few centuries, until pictures 9 and 10 were added.

Sri Aurobindo often said, "our yoga begins where others end."

He made an interesting distinction about this - we are in Ignorance, Avidya, when we begin and the end point both you and he describe is one where Avidya ends.

So in a way, he - and all mystical, contemplative, yogic paths agree (I can't for the life of me imagine how your friend who gathered all those maps didn't see this blisteringly obvious fact). I have practiced the yoga of sound for some years and I agree with your description of it's extraordinary simplicity and power, but I would put the universality even in a simpler way:

Recognizing the identification with a particular set of phenomena, and releasing that identification, I am."

There's a long line of Buddhist, Vedantic, Tantric and other sages who say for "ripe souls," that's all that's needed.

in fact, that happened to me spontaneously when I was 17.

But it didn't "remain." Hence, the subsequent decades of practice, including the yoga of sound.