1)
Why did he mention his fathers?
1.
Ibn Ezra: You gave Chochmah to me more than to other Chachamim, because my fathers were Nevi'im.
2.
Malbim: You gave to me Chochmah and Gevurah to stand in Heichal ha'Melech, in the merit of my fathers from Beis David.
2)
Why does it say "Hodatani" (singular) and "Hodatena" (plural)?
1.
Malbim: He and his friends requested to inform them; Hashem informed only Daniel, in the merit of his fathers.
