JSA/Work Programme Sanction

The jcp adviser calls the provider whilst you are there, you become a reference number, the jcp adviser issues you with the appropriate letter that mandates you to attend, the person with the reference number fails to go, the reference number is known to link to the said job seeker so therefore dma action can be taken. not really that hard to trace.
As for you refuse to take the details of the interview or you state you are not going, the jcp adviser notes the system that you have failed to take the details. When doubts are sent to a decision maker it is up to you to prove you have good cause or reason for failing to attend.

You say didn't know where or when, JCP adviser will state well you failed to take the notification when issued to you! This method has been used and resulted in sanction.

Easier option would be to go, surely any help to get into work should be accepted?