Posted 2011-02-20 01:48:20
I fly out of BKK approximately every month, and each time, the immigration officer keeps the departure card. Unlike other countries, it is not stapled to the boarding pass for the airline to hand it back to immigration.
I cannot imagine a scenario in which the immigration officer forgot to take the card or stamp the passport, but maybe it was very early in the morning or very late in the evening. I have learned to never rule anything out. As tourists, you might not be aware of the procedures and that you have to actually look into the passport to ensure that the stamp is there, but you are indeed responsible if there is a mistake.
If the immigration officer didn't take the card, it is possible that he also didn't enter the departure into the computer. And this is what makes the difference: If the departure is in the computer, all is fine. If not, there will be trouble. This is where I have to admit that I never heard of a case where this happened. In fact, if she is still in the computer as being in Thailand, she must be arrested for overstay when found - even if she is found while entering the country. Because then, it means that she left the country illegally. And that spells trouble.
You don't know what the computer says, and whether the nice immigration officer at departure updated it to show that she left. But that is the important part, I believe.
Embassies are under the Ministry of Foreign Affairs, while immigration is under the Ministry of the Interior. Therefore, and to make matters worse, I don't even think the Thai embassy in Vienna can help you - but then, I am not a lawyer.
Best is if she changes her name, dob, and nationality. That's not a serious advice, of course. But I would expect trouble upon arrival, and have all documents ready you can think of. Also, the Austrian embassy in Thailand is very helpful, and it may make sense to alert them in advance. If she gets arrested upon entry, the embassy will be notified anyway, so it is good to prepare them.
Gee, whenever you travel (and not only to Thailand, it's a general rule) make sure you get the passport stamped. It's really the basic ABC of travelling. But I guess you kow that by now.