All objects in the world derive their existence (satta) from brahman or pure consciousness. So it is correct to say that they are dependent on consciousness. But this is not the same thing as saying that their existence depends on the observer or knower. The knower is the mind with the reflection of consciousness in it and not pure consciousness. Of course we say that everything is a creation of the mind. But that only means that we react to objects in the world according to our mental make-up. Even after realization, when there is no mind in the sense that there is no mind of the kind we the unenlightened have, the jnAni still sees the world of objects, though he does not react to them and consider them to be good or bad.
(from an Advaitist dialogue)
Although what the above quotation says is correct at one level, from the viewpoint of strict non-duality it would be said that there is no observer or knower (or thinker), only arisings in consciousness, since there are no individual, or separate observers, thinkers, etc. : there is only knowingness, observingness, etc., as modificatons in the one consciousness. There is only consciousness. What is called mind collapses into consciousness; its reality is consciousness.