using whirlwind around a friend on a server, the friend died of the explosion and it didnt report it in chat, it also didnt spawn a VanillaDeathChest - I have a feeling its the weapons problem but I an open an issue on vanilladeathchest if you think otherwise

Honestly sounds like it could be their issue. It might be that VDC doesn't know how to deal with the deaths? Not sure, but I'll look into it 🙂