In a fire on my property. Anyway should friend contact a att

my insurance said that if he was ta resident, ( friend is not resident) . However when I brought up what is to be done with his medical bills, claim rep now says friend was a resident and was the one cooking when fire started, so claim would be denied. It was never stated that freind was cooking, I had been caring for my dad, with some temp help and something was left on stove, but not sure by who. what should a friend of mine do that was injured

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medical billing claims