It used to. We don't consider DIDX- codes to be catalog numbers because they're not assigned by the publishers/labels; they're manufacturing IDs from the plant that pressed the CDs. There's more info in Secret Squirrel's and Anders's posts in this thread:
https://vgmdb.net/forums/showthread.php?p=9529
(This album is one of a few cases though where the DIDX- code is actually printed on the disc label too, not just the inner ring.)