Tzar'ah and Eshta'ol are in Yehudah (15:33)!
Rashi: Dan's portion was nearby. 1 Malbim
Yehudah was in the south, and Dan was in the north, like it says "Kol Yisrael mi'Dan v'Ad Be'er Sheva" (Shmuel 1 3:20 and elsewhere). Rashi (Devarim 33:22) says that initially, Dan received in the northwest, and later conquered also in the northeast! Perhaps he means northwest of Yehudah (refer to 19:41:1:2). Also, Shimshon was between these cities (Shoftim 13:25) when Ru'ach Hashem was aroused in him [to confront the Pelishtim]. Eretz Pelishtim was near Egypt (Shemos 13:17, Yehoshua 13:3), southeast of Eretz Yisrael. Did Eretz Pelishtim extend until to the north of Eretz Yisrael?! (PF)
The prefix Vov in 'v'Nachalas' means or (or the text should say 'Oh'). Metzudas David gives two answers; each suffices by itself. (PF)