As an ATPL student my view is that the captain should not be reported,he is in charge of the aircraft and in my eyes can do as he pleases,the only person with any right to argue the point is the first officer.(No offence cabin crew)
If I am fortunate enough to be a captain one day I will certainly let kids visit the flight deck.
IF THE PEOPLE IN THE TERMINAL DO THEIR JOB PROPERLY THERE WILL NOT BE ANY"BAD GUYS" ON THE AIRCRAFT. 
As for the DFT.....Bunch of desk jockeys making up rules for the sake of it,the events on 9/11 were not caused by a child on the flight deck,they were caused by brainwashed simpletons gaining access to the flight deck.Judging by the chaos they caused,I for one am sure a locked door would not have stopped them.
BIGEARS IS RIGHT -COMMON SENSE OVER RULES.