1988 LMC Very Odd Incused Area On Rev

this one is illogicly odd to me, I say that because in order for it to be incused it had to be raised on the die (or a pm hit) BUT the clearly seen die scratches tend to rule out a hit? although it has that snow plow look to the edge some die scratches continue uninterrupted right up and over it. its clearly a die break/crack at the rim and continues in along the middle of the bottom step and around as seen. there is also a crack on the left side of the memorial. I dont think its a collapsed bubble? but I cant figure out as to how it could be incused with continuos die scratches running up onto the field?
is it poss say a loose snow coned shape piece broke out of the die and when struck, being loose, bounced upward and made the incused dent? (did I get too far outside the box on that thought ? lol )
just find it odd that those tiny die scratches dont seem to be distorted or flattened out if it was a hit? could those scratches still be so defined if it was struck through something? its incused, yet has a raised above the field like a die crack? ring with die scratches running over it,,,meaning the area was worked on and should be higher on the coin not lower?
you guys'ss (lol) better educated opinion on this one as to how this could be would be greatly appriciated as I cant come up with a logical scenario as to how/why....
As always Thank you!! you guys amaze me with what you see and can tell just from pictures and the knowledge of what it is
*** COOP cant email this q seperate but was wondering with your awesome pic file if you have anything showing the tools used to work on the dies as their bieng used? as thinking just of a dremel tool how small they must be and are they power? or hand operated etc? just wondering.. Please & Thank you