The teen's death has now been referred to the Coroner.
The explosion was caused by a cigarette being lit, igniting flammable vapours on their clothes after they had allegedly been sniffing petrol or LPG, a fire investigator said at the time.
"They've gone upstairs in the house and lit a cigarette or something like that and when they've lit a cigarette it's ignited,'' he said.
A petrol can was found outside the back of the property.
Friends of the teen paid tribute to their friend on social media.
"Rest in peace Kelly Amani. Precious soul gone too soon. Now [you're] in good hand. Fly high, beautiful.''
Another friend said he was praying for the family.
"Until we meet again.''