Is it appropriate for a father to ask his children (aged 14 and 16) to travel alone to meet him at the train station, knowing that he is not punctual?

Sons must obey their father by coming to him unless it involves disobedience (to Allah), even if it is a journey. The presence of a brother with his sister on a journey is sufficient if the journey is safe, as some scholars believe that an adolescent is old enough to be a mahram. However, if the journey is unsafe, a close mahram relative must travel with them to ensure their safety. If no such mahram is available, the father is not permitted to order his daughter to travel to him if it entails dangers, and she is not permitted to obey him in that instance.