A 391st BG account of 23 Dec 1944 here:
https://www.391bombgroup.org.uk/ahrweiler_mynn.php. Perhaps it gives a bit more insight.
Also check
https://catalog.archives.gov/id/91156635?objectPage=2 which has 42-95878 with pilot Capt. Wilbur Cox as a 1st Pathfinder loss on 23 dec 1944.
Other references give Garbisch in # 878...
Regards,
Leendert