Taiwan and US dual citizen ship

Hi,

I'd like to know if this is true or not.

So this guy is born and raised in Taiwan, came to the US when he's 14 and stayed here so he can avoid military. He got his US citizenship, he is over 36 so he no longer is required to do the military and went back to Taiwan for the first time, however he said at the airport he got caught that he did not do the military and was issued not to leave the country untill he goes to court and pays a fine.

He's been there since Nov 2024 and have been to court 3 times already. Now he is waiting for the judge to rule the amount of his fine so he can pay and leave.

Has anyone heard of this? Even if you're dual citizen and over 36, when you enter you get caught if you avoided the military.

I'm asking because my friend who has a Taiwanese husband is in the same situation and she has not heard of such thing. I want to know if he's lying so he can stay in Taiwan longer with his family. He's my daughter's father and has visitations and responsibilities here so wondering if this is true or not cuz I am not taiwanese and have no clue..

When he got his US citizen, he changed his name and I'm sure he used only his US passport to get in so now I am wondering how the immigration found out he's dual citizen.. I don't think the immigration are that advanced yet. Any thoughts on this?