Cypherdecode,
My guess is that the analog line you are connecting to the Tenor is either not really providing correct reverse battery answer supervision or maybe the Tenor is not recognizing it.
You stated that it takes 23 seconds for the call to connect, but do you actually get a call connect from the Tenor after this time or does the user simply hang up? If they hang up, then what I said above is true in that the Tenor is not seeing the reverse battery from the PSTN line to say that the call is connected. Try setting the cassig to loopstart only or loop start forward disconnect, then set the supervision to answer and the answerdelay to 60 and see if that helps.