I don't want to distract anybody from the intention of this thread. But, challanged, I doubt that a book, released (?) in 2002 can be a source for quotations from the the times before 415. It would be interesting to know, which source Krantz got the quotations from.
As You have cited, there are certain sources on the life of Hypatia, none of which has these quotations. But the website You referred to can be of help, of course. When you go one step up to the main-page on Hypatia, different resources are linked. The article of the so-called Suda can be read, the ones by Socrates Scholasticus or John.
And ... Elbert Hubbard's account on her! That's, imho, where problems start. Because you can find the quotations there. Hubbard seems to have written something like a novel. I don't know, because I haven't and don't have the time to check. But if You compare Hubbard's text and the only surviving, very thin, sources ... well, Hubbard's might have channelled some information, but the rest cannot be but pure fiction.
And there we read:
Hubbard wrote:"All formal dogmatic religions are fallacious and must never be accepted by self-respecting persons as final," said Theon to Hypatia. "Reserve your right to think, for even to think wrongly is better than not to think at all."
Two quotations found beneath each other. Both said by Hypatia's father. Check it
here, but mind, it's not the book You check, it's a website with what looks like an extract.
I guess You wanted to know "manipulation of what exactly" more than You wanted to read about the problem with sources and alleged quotations. But asking where quotations came from can be rewarding in getting to know the truth.
A woman from around 400 C.E., murdered by "the christians" is portrayed as 1. enemy of dogmatic religion 2. free thinker 3. "probably an atheist". The bias seems to go towards 1. making a pagan, "probably atheistic" "saint" and martyr 2. outlining intellect-hating christianity 3. attributing resentments against "dogmatic religions" to someone who could be a saint or martyr.
Nothing against Hypatia, atheism or resentment against any religion (as long as they're no substitution of arguments). But until I learn about real sources, I think it's a shady business. Unworthy to someone who seeks the truth.