Part of Undivided Awareness
I understand why a nondual teacher might want to deny that our minds are made of parts.
Because we experience nothing but undivided awareness.
And any seeming division is a conceptual fabrication.
But we can know this experientially and still recognize that conceptually our minds are made of parts.
Just as we can know that there's nothing but ocean and still recognize waves.
And we can use parts as a conceptual map to better approximate what is true without forgetting that the map is not the territory.