What is the meaning of "Lo Zaru mi'Ta'avasam"?
Rashi #1: They did not become strangers to their lust; they attained all their desire.
Rashi #2: They did not distance from their lust before punishment came upon them.
Radak: This is like "v'Hayah Lachem l'Zara" (Bamidbar 11:20); the Targum is, until you will detest it. They did not loathe the meat, for "it was still in their mouths 1 ."
Malbim: They did not cease their desire (and regret). This shows that their sin was due to denial, and not due to desire (refer to 78:29:1:2).
Radak did not explain why Hashem's word was not fulfilled. Perhaps he explains like Da'as Zekenim (Bamidbar 11:33) - Beinonim died while the meat was still in their mouths; Resha'im died after suffering for 30 days. (PF)
Why does it say "Od Achlam b'Fihem"?
Rashi (from Tanchuma Beha'aloscha 16): While the meat was still in their mouths, "v'Af Hashem Charah va'Am" (Bamidbar 11:33). "Veha'Safsuf" (ibid., 4) are the elders - "Esfah Li Shiv'im Ish" (ibid., 16).