Totem of Undying did not work

My partner went into the nether and was jumped by Piglins and a Ghast (that's normal, no problem), but his totem did not pop when he got killed by a Piglin (not the void nor \kill command), (yes it was in his left hand) leaving him stranded with no gear, with his gear way beyond the 5-min time limit to get it back before it despawns. How is that a valid death?