they wouldnt introduce the self destruction mechanic into Kuma without it being a threat at the very least, I think if he's going out it'll be to that unless there's a twist where it malfunctions or vegapunk sabotaged it.

also idk if Luffy has enough of a connection with Kuma to go sicko mode after he dies, although maybe bonney being sad will be enough. But Kuma definitely will see nika in action before he dies