Underaged children being interviewed:
Children under the age of 11 usually are not suitable to interview under journalistic ethics. However in certain cases, children are the only witnesses able to talk about it. Children also have a somewhat poorer judgement than most other people due to their still developing minds. What does one do in this situation?
Sometimes there is no choice. In Myanmar for example, journalists are deported and even jailed. So there may be no choice except to go undercover as someone else. This way has its own potential hazards. You could be arrested under espionage charges(Spying). Is it a worth while risk to take?
It is in the ethical code. No bribing interviewees. But you've got the do what you've got to do when no one want to talk about anything even remotely related to the situation. The cases are rare but there are some journalists who do it.