Here’s an excerpt from Miller’s article:
As Walsh correctly observes, Rand here  ascribes a series of alleged statements to Kant but does not provide direct quotations in support of her interpretation. The source of the foregoing interpretation is Rand’s essay, “For the New Intellectual,” which is a polemic and a manifesto for Rand’s intellectual followers rather than a work of scholarly exegesis. This work offers a broad-brush history of philosophy containing a number of unflattering cameos of famous thinkers, of which the above sketch of Kant is typical. This approach leaves Rand open to the charge that she is misrepresenting Kant or misunderstanding him, or both. Indeed, I think that Walsh has compiled detailed and persuasive evidence that the explicit statements regarding reason and reality which Rand has attributed to Kant do not agree with Kant’s own characterization of his position.
However, even if one agrees with Walsh that Rand attributes to Kant claims regarding reason and reality that he does not explicitly make, there remains the more important question: has Rand accurately identified the fundamental implications or presuppositions of Kant’s metaphysics and epistemology—regardless of whether Kant acknowledged them as such—when she asserts that “the entire apparatus of Kant’s system—[rests] on a single point: that man’s knowledge is not valid because his consciousness possesses identity.”  The first question, then is whether Rand is here offering a fundamental insight into Kantian epistemology or whether, as Walsh maintains, this is “a point of misinterpretation.”  The second question is whether Rand has good reasons for rejecting the Kantian view. These are the principal question which I wish to pursue in this commentary.Miller rejects Walsh's view that Rand has misinterpreted Kant. According to him, Rand has passed a correct judgement on Kantian metaphysics, even though she has not given any evidence to support her position.
But I am not convinced by Miller’s assessment of Kant’s metaphysics because his analysis is quite shallow. He has tried to analyze a couple of quotes from Kant’s works and he makes references to Aristotle, Plato and even Schopenhauer, but all this is not enough to dethrone Kantian metaphysics. Miller does not offer any concrete evidence to make his case.
1. Miller refers to a paragraph on Kant in Ayn Rand’s essay, “For the New Intellectual.”
2. Introduction to Objectivist Epistemology
3. Essay by Walsh