1)
Who came to whom?
1.
Rashi: Na'aman came to his master, Melech Aram. Radak - this was after his wife told him the girl's words.
2)
Why did Na'aman accept her words?
1.
Malbim (3): Na'aman understood that his Tzara'as is due to the Navi's anger. He thought that it is because Na'aman killed Melech Yisrael.
3)
Why does it say "ka'Zos vecha'Zos"? It is enough to say ka'Zos!
1.
Malbim: He made inferences from her words. Due to the anger of [the current] Melech Yisrael, because Na'aman killed the king's father, he commanded the Navi to afflict Na'aman with Tzara'as.
