[mothered]

I'm thinking of saying the battery exploded and I had to dispose it, do you think it'd work?

That's one of many options available which has a "chance" of succeeding, but due to Its value, they'll most likely be adamant In requesting Its return.

Also, will anything happen to the original user of the phone?

It depends If they decide to take action by deeming the phone as a write-off.

Who's the company?