Is 2 Maccabees 7 an interpolation?

2 Macc 7:28 is often touted as proof that creation ex nihilo was taught before the 2^nd/3^rd centuries when many scholars believe the doctrine first came about. As I wrote in a previous post:

Indeed, the closest text accepted by Christians as canonical would be 2 Maccabees 7:28, part of the Catholic canon: “I ask you, son, look to heaven and earth and, seeing all things in them, be aware that God made them from non-being and the race of men began in this matter.” But in the phrase, “God made them from non-being,” this “non-being” dos not express absolute non-existence, only the prior non-existence of the heavens and earth. They were made to exist after not existing. In Wisdom of Solomon 11:17, the author speaks of God’s “all-powerful hand which created the world out of formless matter” (Greek: amorfos hyle). This term does not mean the world was created out of nothing, as scholars, such as Jonathan Goldstein state that there is no pre-rabbinic Jewish text that can be proved to assert the doctrine of creation ex nihilo (see his “Creation Ex Nihilo: Recantations and Restatements,” in Journal of Jewish Studies 38/2 [1987]).

However, another possibility is that the text might teach creation out of nothing, but the entire chapter is a later interpolation. To read an interesting, well-argued article on this very issue, see Daniel O. McClellan, "A Reevaluation of the Structure and Function of 2 Maccabees and its Text-Critical Implications” (available online here).