Interesting... I googled "Can a heart attack feel like a toothache?" Anyway, yes, what seems to be a toothache can actually be a cardiac event.
In the event that Jonathon was found deceased when the 29 year old went home after work...
or Jonathon took or was given (knowingly or unknowingly a drug) and subsequently was found dead...
or of Jonathon had a pre-existing cardiac condition and, due to the work being strenuous, he died suddenly...
I'm not saying I think this is what happened but just speculating. I know if I found a kid, who was working for me, dead; I would call 911 immediately. I think most people would. I have to think anyone who
didn't call 911 under such circumstances must have felt
directly or indirectly responsible for the death; whether Jonathon had a heart attack or not.
There's no shortage of links on the subject but here's two:
"Heart disease and lung cancer can also cause toothaches. In some cases, toothache may be a warning sign of a heart attack.
Heart and lung disease can cause toothache pain due to the location of your vagus nerve. This nerve runs from your brain to the different organs in your body, including your heart and lungs. It passes through your jaw."
Toothache: Causes, Symptoms and Diagnosis
"Pain from a heart attack can spread down both arms and to the jaw or head. Some people report a headache, earache, or tooth pain as a symptom during a heart attack. You can experience this pain with, or without, chest pain when you have a heart attack."
Heart Attack Warning Signs You Should Not Ignore