Hello! I was able to make a minimum reproduction that you can try at this private code: 9635-1709-8316
This needs at least 3 players to reproduce. There are 3 player spawners with 2 players on a team, and the 3rd person on the other team. Inventory is set to keep on death. Down but Not Out is disabled.
1 person will be using their Infinity Blade, their teammate will get killed by the jump attack, and the third player will kill the player with the Infinity Blade during the jump attack.
If it needs to be published for you to access it just let me know and I can do that.
It is quite easy to kill your teammates with the jump attack, the positioning is not very particular.
If the person using the Infinity Blade gets killed while using the jump attack, that is when they lose their inventory. It is dropped on the ground with the Infinity Blade. Since you don’t keep the Infinity Blade on death, even if the Island Settings are set to keep. I imagine the rest of the inventory is getting caught up in that dropping process for some reason.