Possibly fear or stress. It’s unlikely that the vaccine would have caused his death in minutes after its administration.
I’m not a big vaccine fan, mostly because I think the vaccine is just unnecessary and adds psychological stress to the lives of people who are already stressed. I think this is a case in point.
However, to suggest that the vaccine is so toxic he keeled over immediately, not even having had an allergic reaction, is ridiculous.
Probably Anaphylactic shock.
He was probably a candidate for a heart attack but the shot probably caused an immediate constriction of a coronary artery.
The covid vaccine is so toxic, but I am still alive 12 weeks after 2nd shot of Moderna. Heading to the Gym in 5 minutes for my daily exercise. Here is a sample.
https://www.youtube.com/watch?v=I55ZxIwbuOU
In 19 years I intend to make a new exercise video (I will be 100) and post it on youtube which may or may not be alive in 2040. But the flat earthers will tell me the long term effects of vaccine might take 20 years. OK so then I will make another exercise video at age 101. But I refuse to live past 103 (age when my mom passed away). SO please do not predict long term effects of covid vaccine to show up after 24 years.