Duy Quang Phan puzzlement

The NCMEC just added a poster for the 1992 disappearance of Duy Quang Phan. Except they spell his middle name “Tuang.” The Polly Klaas Foundation has a page for him too. He was seventeen when he vanished.

I’m a little puzzled by this. Duy was swept out to sea while swimming at a California beach. An obvious drowning victim, but the NCMEC doesn’t usually post those. And they’ve got an age-progression for him too. (It says APed to age 45 but I think they really mean 35. He would be 34 right now if he is still alive.) Is there actual evidence that he might still be alive, I wonder? Or are his parents just deluded, or do they think his body might yet be recovered?

*scratches head*