Rafael,
i saw the capture and agree with the NPS is the one that is rejecting the authentication, i am not sure if NPS has a debug / log tool but let's investigate both of us, :)
there are a couple projects running to make this possible, however you can break your CMX box.
https://serverfault.com/questions/425020/authenticate-linux-sshd-with-tacacs-cisco-acs
good day Rafael,
some pieces of information would be great to address this issue.
from the controller enable the following:
debug aaa all enable
debug client <mac address of test machine>
once those are enable try to connect the test machine ...
