[Freeswitch-users] Getting DTMF during Fifo

Hi I created a call senter using fifo. I used a LUA script to detect the caller position in the queue, as explained in the wiki. I want to play a file to tell the caller to enter his pin number (or SSN) and I cannot find any way to do that. I have his UUID but all the samples to get DTMF digits are from the session. How do I get DTMF digits if all I have is UUID? Thanks Eli