After a couple of back-and-forths, B6 sent me to this:
https://www.singaporeair.com/saar5/p...eage_Claim.pdf
It says to make sure I have waited 6-8 weeks after flight before filing this... I'm in the 8th week so I'm going to wait another week or so then fill out the form... which it says will take another 8+++ weeks to process.
What a PITA.