1)
Why does the Torah here call Gad's son Tz'fon, whereas in Vayigash, it calls him Tzifyon?
1.
Ba'al ha'Turim (citing the Pesikta Zutresa, Sotah 13b): The Torah calls him "Tzifyon", from the root 'Tzafun' (hidden), with an added 'Yud', because Moshe, who received the Aseres (Yud) ha'Dibros, was destined to be hidden (buried) in his territory.
