In my book I gave many examples of Maimonides misquoting verses from the Pentateuch and the rest of the Bible, which I attributed to Maimonides citing from memory. It is not uncommon for medieval writers or even modern ones to misquote verses for this very reason. I don’t know why Buchman thinks Maimonides should be immune to this.
Buchman believes that it is more plausible to assume that Maimonides had alternate versions of these biblical texts, and this explains the misquotations. This is an untenable suggestion. To begin with, many of the misquotations are combinations of verses or Maimonides citing the wrong verse. As for the other misquotations, where only a word or two is different, in many of these cases Maimonides cites the verse accurately elsewhere, even in the same book. Furthermore, when it comes to the Mishneh Torah we know that he had access to the Ben Asher text, which he examined carefully with regard to the Pentateuch.