The Nondual cannot be expressed in duality

A man after reaching the surface cannot say "I am under water". The two are contradictions in terms.
The experience of the Nondual state does not admit of speech and expression.
The existence of speech or expression precludes the experience of the Nondual.

Does a true jnAni say
"I am God." ?

Nay, the experience of the Nondual, although it is that of
अहं ब्रह्मास्मि aham brahmAsmi (I am Brahman)
does not lead the true jnAni to say these things.

In the Nondual state the experience is only of mergence with Everything. Two cannot exist in that state. There can be no one else who can pay obeisance, nor anyone to pay obeisance to.

The experience on emerging from the Nondual is only "Thine is the Power and the Glory." Complete surrender. All else is falsehood.

That is why Sri RamaNa says, there are only two ways to the Self. Constant vicAra as to 'Who am I' or complete surrender to the Lord. In the dual state, only the latter can be observed. The state reached by vicAra cannot be described in words. It is beyond speech. But humility is associated with jnAna and not boastfulness and arrogance towards the wise.

In the Kenopanishad there is a verse that also shows how the disciple cannot admit to either knowing Brahman or not knowing Brahman. This is to imply that Brahman is beyond Knowledge and Ignorance. One who says he knows Brahman cannot be right (even if he has) and one who says he does not know Brahman cannot also be right because there is nothing but Brahman and it is beyond intellectual apprehension and sense-knowledge.