We are still in chapter 3, where Valliant discusses the claim that Rand was an authoritarian. One of the people Rand "broke" with was her attorney Henry Mark Holzer. Valliant suggests that Rand's splits with people (to the extent they were splits as opposed to just drifting apart) concerned ideological disagreements. He says it is "clear" that philosophical splits were emerging with people, even if it is "not entirely clear" that these differences were the "proximate cause" of the split.
Turing to Mr. Holzer, Valliant suggests that their split might have had something to do with Holzer's belief in strict construction of the constitution. Rand, Valliant tells us, had a more flexible approach to constitutional interpretation. (page 74.)
That's about all that Valliant says. There are two footnotes to the paragraph in question (numbers 52 & 53).
Footnote 52 refererences Holzer's book Sweet Land of Liberty? where Valliant notes that Holzer didn't agree with the "right to privacy" underlying such decisions as Roe v. Wade.
Footnote 53 references:
1. Rand's Marginalia at pages 203-205;
2. An article by Harry Binswanger concerning the Bowers v. Hardwick decision (a 1986 Supreme Court case in which the court uplheld a state's right to criminalize sodomy); and
3. Stephen Macedo's 1986 book The New Right v. the Constitution.
I don't have Holzer's and Macedo's books, but from their titles I doubt they contain information on the Rand/Holzer relationship. Certainly Rand's Marginalia and Binswanger's article don't.
In fairness to Mr. Valliant, he doesn't claim to know the reason for the split, but he leaves the impression that philosophy was an issue. Based on these footnotes it isn't "clear" to me that Holzer's judicial philosophy was a factor.