It seems, tht he had ticket to travel, but when TTE came he could not show to him for verification. and then TTE collected ful fare, and asked him to get refun.
Thus he has to file the TDR.
You need to file TDR :
Go to stn, with application and ticket and the receipt of what TTE gave, file the TDR and...
more... you will get refund. If it is e.ticket, your account will be credited, if it is PRS ticket, you will get 'refund warrant' Time varies: four days for e-ticket, three weeks for PRS ticket at minimum.