um... off subject somewhat, but ive dropped phones while on the charger, and the battery popped out, and the phone stays on. my ascend will boot on with no battery, just charger/cpu connected, im pretty sure the same goes for the esteem.
to the op, i assume you didnt get metro insurance, hence why your hitting up lg? otherwise take it to your closest metro and throw it in their face (only if they deny you for any reason) because if noone here can get it going, metro sure as hell wont be able to.... (last resort) and if they do get it booted and find out its rooted, tell them you got no clue wtf happened, it came like that. metro has been dealing out ALOT of refurbished ones lately, trying to pass as new (in my area) as a friend and myself went to go get him one, and super user was installed XD.
if you need help going that route, im sure everyone here will help you out on what to say.