No in c) I speak about the passkey in the tracker announce URL, not the username / password combo to log into his account.

He can find his tracker announce URL in his Profile, it looks like:

http://tracker.gaytorrent.ru:2710/here_the_passkey/announce

or

http://tracker.gaytorrent.tw:2710/here_the_passkey/announce

or

https://tracker.gaytorrent.ru/here_the_passkey/announce

where "here_the_passkey" is a long series of numbers and letters.

If you edit in your torrent client the tracker announce URL (properties) to have his passkey instead of yours, your upload and dwonload will count towards his account.