Either there was some underlying health issue with the baby, or there is foul play other than neglect involved.
Welcome back to the tread. I can’t believe you think a 23 day old can handle heat stress the same as an adult.
I’d call your attention to other replies in this thread that prove you wrong. I’d even go and grab some links that medically prove a 23 day old is unable to regulate extreme heat conditions, but what for?
Your mind appears made up.