Is that raised under his chin? Also, from the left side of what your calling a crack I can see a slight line that goes up to his cheek. Is that raised as well?
Along the neck could be MD that cracked. Just guessing as it’s not raised. The raised mark on his check is probably a crack. It’s fairly straight but it’s not plated. I’d keep that coin.
And this previous post of mine The little crack on the 1982 is an indicator for no P, late stage https://www.cointalk.com/threads/brothers-reunion-2016.387891/
It looks like there is some engraving work done under the chin and at the prominent point, a die chip/break. Nice specimens @Heavymetal !