Geordie613 and Lilmod,
I think I have the answer. Rashi on that posuk and the Gemara in Shabbos 145b limit the application of the posuk to Yehudah. ??? ????? ???? ?”? ??? ?? ??? ??? ?????? ????? (?????? ?, ?) ?? ????? ??? ??? ???? ???’ ???? ????? ??? ???? ???? ????
Yehudah refers to the portion of E”Y that was held by the Malchus Bais David after the split. So it may very well be that no person walked in Yehudah for 52 years, but other parts of E”Y were still populated and still had Jews.