Hi,
in your script you probably have a Hold step, folled by a Delay step. Set the value of this Delay step to 120, then using a Goto step, jump to a place in a script where you collect all the digits and the result is placed to a Call/ECC variable which is then shown on the CAD.
This, of course, won't work if the caller disconnects, because the call will never reach the agent.
A better option would be to store these reference numbers alongside with the call metadata (ANI, date and time of the call etc), probably in a database table. Information from this table would be presented in a form of a web form - embedded in the CAD, perhaps.
G.