Call-back with announcement/confirmation -Direction Needed

Hey, I want to implement call back feature but I struggling with where to start.
Here are the step I want to happen

  1. Call an extension, (this is on another system, and could have an IVR in front)
  2. Repeat - Play a message (You have a call back from Name Name @ please hit # to accept
  3. Wait for DTMF
  4. Call the person requesting the callback

I got 1 & 4 to work, And 1&2 with call files,

But after playing the sound it hangs up and wont connect, and I don’t know who to get it to wait for a DTMF tone before calling the other party

Any ideas?