Could you provide a source of this information, please? Reports I've read recently don't speculate about what happened at the scene of the crime, other than Taylor coming at the perps with a machete in hand, which is based on the girlfriend's story. Your post paints a very different picture, and I would need to see further proof before accepting your conclusion. If the house was presumed empty, the locked bedroom door would be just that, a locked door, which in the perps' eyes, might be hiding loot. No need to assume people were inside.
Edit: Grammar & clarity