I thought ping in an automobile engine was caused by the ignition firing too soon, and the piston is not all the way up.
So the piston is trying to compress an explosion that already happened. The ping noise is your connecting rod bearings slapping around.
I never heard of secondary flame fronts. But I am not an engineer.
Doesn't matter what octane you have, you can make an engine ping by increasing the timing too much.

I understand about the higher octane slowing the burn process down.

Check this out, a top fuel dragster only makes around 500-600 revolutions of the crank to get down the 1/4 mile.