Yoga does leads to the final truth.+

Advaitic truth is the ultimate truth. Yogis, mystics, and religious teachers do not accept the path of wisdom because it pries into the truth, the source, and the validity of the knowledge they claim. Therefore, it is the most difficult part of the study of the Advaita.

Manduka Upanishad:~ Yoga is in the sphere of duality and is unnecessary to one who knows non-duality.

Brih Upanishad: page 32:~ "Yoga does not yield truth or liberation."

A yogi cannot attain realization, because he thinks his body to be body and world to be world and fails to see them as consciousness and thinks his experience of Samadhi is because of his individual effort.

One who is in Samadhi will not know that this universe as the consciousness; therefore yoga is not the means to Self- knowledge or Brahma Gnana or Atma Gnana.

In Samadhi the yogi knows nothing and sees no universe; so if there is nothing but blankness. The blackness is not the Advaitic wisdom.

The yogi does not know the nature of the universe. If the universe is not seen in the Samadhi then there is no need to use the word Atman and Brahman. The yogi is unaware of the truth, which is beyond form, time, and space.

By shutting his eyes in Samadhi, the yogi does not know the universe, which confronts him. Hence, the universe can't be known as the Soul or the consciousness through yoga.

One is in a non-dual condition in deep sleep or Samadhi, One without a second, true, but he did not know it at the time. He says only in the waking experience afterward. Hence, there must be an inquiry so that you find non-duality whilst you are awake so that you can see nonduality at the time not afterward. Hence, the need of inquiring into the nature of the universe and knowing it as the Soul or the consciousness whilst one is awake, and not during sleep or Samadhi.

Advaitic truth is the ultimate truth. Yogis, mystics, and religious teachers do not accept the path of wisdom because it pries into the truth, the source, and the validity of the knowledge they claim. Therefore, it is the most difficult part of the study of the Advaita.:~

Panchadasi: ~ The impossibility of yoga arriving at a successful end to its practices. -P.509 v, 109

One has to investigate “Why Yoga is right and the other paths can't give the truth?" Or how is one to know that Yoga leads to the final truth?"

Yogi shuts his eyes the world confronts him and then has the temerity to declare that it knows the world to be Brahman! Because he has not inquired into it, he knows nothing.

Yoga helps the yogi by giving him the feeling that the world is not worth bothering about, it detaches him from the world; it makes him treat the world as a dream. It does the same to his ego to some extent because he becomes indifferent to what happens to him. But this is only a feeling, he feels these things only but does not know that the world is merely an illusion. Such knowledge can come only through Advaitic wisdom in no other way.

Sage Sankara said:~ -Neither by the practice of yoga nor philosophy, nor by good works nor by learning, does liberation come, but only through the realization that Atman and Brahman are one in no other way. (1) Vivekachoodamani v 56, pg~25

Sage  Sankara’s wisdom is nothing to do with religion and yoga. There are two kinds of audiences - the ordinary ones who desire the transitory heaven and other pleasures obtained as a result of ritual sacrifices, and the more advanced seeker who seeks to know the truth beyond the form, time, and space. Religion and yoga are meant for the first audience, to help lead their followers along the way. 

Sage Sankara’s Advaitic wisdom, with its emphasis on the Advaitic wisdom, is meant for those who wish to go beyond such transient pleasures.

If the Self is the Soul then: ~

Where is the yogi? Where are his chakras? Where is the world in which he exists? Where is the divine light? Where is the divine sound? Where is the divine vibration? What needs is there to say more? Noting from the Soul because whatever seems to emanate from it, is non-different from itself. There is no second thing other than the Soul, which is present in the form of consciousness. One should not mistake Self (Soul) for the ‘I’.

That is why the yogi cannot be Gnani. It is the difference between feeling and knowledge. The feeling of the yogi that the world is unreal may change tomorrow because all emotions are liable to change; and the fact is that yogis do change, as when going after women they lose their sense of world unreality though previously they felt it. : ~ Santthosh Kumaar