Since you are authenticated as “archonfreak” and not the channel owner “imcoty” you will have to use the user subscription end point: GET /users/:user/subscriptions/:channel
For example, using the oauth token you supplied in your post: https://api.twitch.tv/kraken/users/archonfreak/subscriptions/imcoty?oauth_token=7vu4yscpol8l1s6dh2acqbv4k9apc3b
vs a channel (lirik) you are not subbed to:
https://api.twitch.tv/kraken/users/archonfreak/subscriptions/lirik?oauth_token=7vu4yscpol8l1s6dh2acqbv4k9apc3b