Last year, I left a CD holder case with 12 of my favorrite CD's in the seat-pocket on my flight from YVR -OGG.

I guess I was so excited to be in Maui, I got up & left it. while I did get thru to lost articles, and they were very helpful & sympathetic, it was never returned. A bit different from a suit bag,
I guess, as I was at the mercy of the next person in the seat, and the cleaning staff at YVR. (The planes apparently are not groomed in OGG)
Very sorry for your loss!