You also sent this in the correct order:
PASS oauth:twitch_oauth_token NICK twitch_username
and received this?
:tmi.twitch.tv 001 twitch_username :Welcome, GLHF!
:tmi.twitch.tv 002 twitch_username :Your host is tmi.twitch.tv
:tmi.twitch.tv 003 twitch_username :This server is rather new
:tmi.twitch.tv 004 twitch_username :-
:tmi.twitch.tv 375 twitch_username :-
:tmi.twitch.tv 372 twitch_username :You are in a maze of twisty passages, all alike.
:tmi.twitch.tv 376 twitch_username :>
are you able to connect to a regular channel to send and receive regular PRIVMSG?