His chakra was being blocked by that burning seal. If he released too much he would probably die, but hey idk he couldn't take the pain first time around so I doubt he would have survived the kyuubi letting out some chakra.
"When Naruto arrives at Hōzukijo, Mui, the head of the prison, quickly places the Fire Release: Heavenly Prison on Naruto, sealing his chakra. Naruto learns this the hard way after using his shadow clones, Naruto quickly collapses from the pain caused by the seal."
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"An imprisonment technique (禁錮術, kinkojutsu) used by Mui's clan. The ones who are subjected to this technique have a formula applied to them, which will prevent them from moulding chakra and from using techniques. It will also drain them of their chakra at a slow but steady rate. Mui uses this technique on the prisoners of Hōzukijō."
Naruto using the Nine-Tails' chakra is the same as using his own chakra, as it mixes with his when he uses it
He cannot mold kyuubi chakra because it is inside his body. Tenrou doesn't allows to mold chakra. And if you say how he fought with Satori, he used natural energy that comes from outside.