I think that this type of question is really difficult to answer for anyone who has not endured what Jeanne did. Whatever advice we, as outsiders, could give is limited by its contextual nature. I would say that you could go one of two ways on this. You could reflect with the whole, "What would I do in such a situation" and while this is fine, it might not really capture the essence of what the situation is. There's nothing wrong with this, but given the horrific nature of internment, I would want as strong as possible a rendering of how one could survive such an ordeal. I might suggest that another approach to this would be to use the internet as a way to gain some insight as to what survival strategies were employed during that time period. YouTube features many such narratives and stories. If you enter "japanese internment camp survivor stories" and see what results. You might find that what is present can help formulate some very real and definitive points of view on one of the most gruesome chapters in American History.
It seems to me that the main thing that a person would need if they were put in a situation like that of Jeanne Wakatsuki would be patience. It would be important for the person to be able to wait for things to get better.
It would also be important to be adaptable. In a case like that, Jeanne and her family had to adjust to having their lives turned upside down. Adapting is usually easier for kids, so Jeanne probably had an easier time than her parents.
But, in general, the major survival skills I think you would need would be patience and adaptibility. Of course, it's easier to talk about those than to actually have them.