The lid may have compressed her lungs or trachea.
Of course, crawling into a donation box does not confer immortality, she may well have been in poor health anyway and could not withstand whatever added physical stress being trapped in a donation box entails.
Isn’t what you describe “strangulation”, not “suffocation”?
Maybe I’m wrong. If I’m wrong I apologize to the reporter.
To me, if someone’s head is out in the air, and I’m told that person “suffocated”, I’m going to at least ask WTF.