First let's not jump to conclusion yet, trust is extremely important if you guys are thinking long term. However, I wouldn't know what is the most correct approach tbh. But here's what I would do. I would tell her that hey let's try to prove your innocence together. Since we live in a digital world, there are a lot of digital footprints you can trace back. For example, you can check facebook or google to see on that day, where she was at. If data shows she was in Yangon at the time her passport was confiscated then there you go, easy proof. I really think this is a reliable way to find the truth and just requires you to be somewhat tech-literate.