

Actually, according to the article the main difficulty is just the lack of a passport. The article does mention that some legal residents of the USA might be worried that they would nonetheless be prevented from returning if they left the country to act as chaperones for these children, but that’s a purely hypothetical problem so far.
The incident mentioned in the article ended with the passport returned, but if there are other incidents of passports being taken and not returned then I would agree with you.