Why did Yosef approach the members of Pharaoh's household, to plead with Pharaoh for Yaakov to be buried in Kena'an? Why did he not go himself?
Ramban: Refer to 49:29:3:2*.
Moshav Zekenim, Seforno: Because he was still in mourning with torn clothes and sackcloth, and "one does not come to the gate of the king wearing sack-cloth" (Esther 4:2). Ha'amek Davar - As long as the Mes was not buried, Yosef is an Onen, 1 and he is not fit to come in front of the king.
Even though this was after the 70 days finished, and one need not wear torn clothes after the Shiv'ah (YD 340:14), the seven days are counted from the burial (PF). Also refer to 50:10:151:1*.
Why does it say "El Beis Pharaoh Leimor"?
Ohr ha'Chayim #1: They should tell Pharaoh also the order in which Yosef spoke to them, to find grace in Pharaoh's eyes.
Ohr ha'Chayim #2 (citing Yoma 4a): One who tells a matter to his friend, he may not tell it to another without permission.
Why did he say "Na"?
Ohr ha'Chayim: The word "Na" means both a request, and implies 'immediately.' He feared to delay fulfillment of his Shevu'ah.
Why did he say "b'Oznei Pharaoh Leimor"?
Ohr ha'Chayim: They should add matters on their own to persuade Pharaoh to consent.
Ha'amek Davar: The words should enter his ears. Bereishis Rabah learns from here that he hinted to Pharaoh that he is forced to consent (if not, Yosef will reveal that Pharaoh does not know Ivri, and he is not fit to rule).
