Welcome to these forums, Agromo!
The insight that there is “something greater than life in ego” sure sounds like at least Second Tier to me.
My take is that every move from one stage to a higher stage involves a kind of ego death. (Note that we are talking about stages here, not states). The self-sense at each stage has to loosen and give way in order to allow the self-sense at the next higher stage to emerge, rather like a snake shedding its old skin in order to grow.
In this sense, we go through a form of ego-death each time we go up a stage.
But to fall into the inner abyss in total surrender, and experience that there is something greater than the ego, that sounds totally trans-rational to me, or Second Tier at the very least.
Are you familiar with “The Dark Night of the Soul” by Saint John of the Cross? He wrote it around 400 years ago (I think), and it’s very much in terms of orthodox Catholic theology, but it is probably the seminal work about this kind of spiritual death into a higher life.
My own experience of an “inner abyss” was in a dream that’s too long to go into here. My experience of a Self that transcends the ego, however, came during a meditation retreat with my guru. For over a week and a half I was in a state where I was effortlessly aware that everything, every subatomic particle in every nanosecond, was a perfect expression of the Will of God, expressing itself actively in the Now. I was aware of my ego as a tiny spectator of the magnificent whole. Ego was the filmiest of open nets, totally transparent to the Divine Totality. It was the best week and a half of my life. Beyond magical. After the retreat was over it took about a week for me to gently fade back into my “normal” state of mind, but I have the vivid memory of that timeless time outside ego. A Zen saying goes, “After the ecstasy, the laundry.”
And yes, total, ecstatic surrender to the Will of God is an absolutely central part of the whole thing, IMHO 
Well, that’s the short version of my experience.
Now I’m thinking that such an experience might not necessarily entail moving from First to Second Tier. In your case, it clearly has. But a, let’s call it mystical experience like this, of the inner abyss and surrender of the ego, might strike a person at any stage level. That person would understand it at whatever stage level they happen to be at. And this experience might or might not goose them to move up a level.
While a conscious experience of a Self that transcends the ego is at least Second Tier, by our reckoning (if I’ve understood Integral theory correctly), if a person at, say Blue or Pre-Modern had the exact same experience, it might just cement that person into a rigid dogma. Just as an example.
So I guess I’m drawing a distinction between a truly spiritual experience, which you certainly had, and the moving up to a higher stage level. Not everyone moves “up” a stage after such an experience. And if they do, they move up from wherever they are to wherever their next level would be. In your case, you moved out to top of First Tier (I presume) into Second Tier. Or so it seems to me.
Anyway. Welcome to our forum, and very best of wishes. I hope my comments are of some interest to you, or at least entertainment.