What is a self realized soul? Is it someone who has attained god realization?
You are quite correct: a Self-realized soul has attained God-realization. The soul is a spark of the Divine Light. In essence there is no difference, only degrees of awareness. The soul and Atman are the same. Atman and Brahma are the same.
As the human body progresses from infancy to childhood to adulthood and then in death vanishes, so too does the soul in a similar way spanning lifetimes beyond calculation come into Being, takes on a series of outer forms that grow progressively in self-awareness including and up to the human level then begins to expand its Self-awareness beyond the confines of ego and body and, in time, creation itself back to its home in God-consciousness.
At the human level, the stirring soul seeks moksha, liberation from form, from maya, from duality and from suffering. An avatar-a descent in human form of God consciousness in a God-realized soul, is drawn by the devotion and magnetism of the aspiring soul to be guided and empowered to reach the goal of union (yoga) with the Infinite Spirit. This takes place step by step over many lifetimes.
Even though the indwelling Spirit is ever present and ever awake, the soul re-directs its attention to the creation through the body and personality and thus obscures the light of the Soul just as the sun obscures the light of the stars when it rises before dawn.
The light of God which is the substance of the soul is very subtle though also powerful as it has given birth to all things. But the outer light of the visible world is gross and can only be perceived by its contrast with non-light.
It takes the help of the guru to begin to dissolve the hypnosis and impact of the blinding and gross light of the outer world.
Be of good cheer for the “dice of Life” are loaded with the inner Light of the soul. “Knock,” Jesus said, “and the door shall be opened.”