I don't know why they told you that, unless they took you literally with the T7, which indeed isn't connected and most likely never will be. But T6 is connected, and has been for a while, on September 8th, I connected (weird to connect at my home airport, but I did) from a usAA operated flight inbound at T6 to a AA operated flight from T4 and walked the tunnel from T4 to T6.