Bummer, I was hoping to be able to re-use some of the ticket's value.

Fare classes are listed below, but as far as I know, the ticket is non-refundable.
SMF-IAH = E
IAH-EWR = E
EWR-HKG = M
HKG-EWR = K
EWR-IAH = K
IAH-SMF = V

Thank you for the help!