Thanks. My failed search was for a substring (i.e. t.co/ISHbpUw) since that's what I see in Google Analytics but that failed; searching for the full URL resolved that problem.
My previous post was also poorly worded. I have no knowledge over whether t.co statistics will be free or not; only that I don't think there is a free way to get them now; I haven't investigated if there were available paid options. The situation of tracking which tweets are giving you traffic is still poor right now, but it might improve in the future.
