This really isn’t that hard to understand as to why they would claim he was born in Hawaii even if he wasn’t...but can’t help you if you don’t get. There are a myriad of reasons why they might do it.
Just go ahead and believe that they told no lies.
If there are a myriad of reasons then it should be very easy to name just one that also explains why they would claim their 9 year old son was born in the United States but their 1 year old daughter was born in Indonesia.