It's unclear what happened to him. After the 80s it seems the US decided not pursue him [1] and per another comment it seems he may have passed in 1999. I haven

It's unclear what happened to him. After the 80s it seems the US decided not pursue him [1] and per another comment it seems he may have passed in 1999. I haven't found much else besides a court case involving his son and wife in 1998. Part of why I posted this was hoping I might peak the interest of someone with more sleuthing skills than I. [1] There was mention in one article from the 80s that he may have been granted a limited immunity as part of providing evidence, which may have helped him avoid a more aggressive effort to have him returned.