Definitely not a die break. That would be a break on the die itself. So when it strikes the blank planchet it would appear raised on the surface of the Nickel. And that is not a Die Clash. It looks incused into the field so it could be a struck through debris issue.
Does the design you see on the obverse look like any part of the design on the reverse? I doubt it so I’m thinking a struck through.
Depends on whether, if the area is raised or recessed, no? Looks like a scratch if you ask me. Better fully images please. The jury is out now.
I came across this coin which was given to me in change. I don't know if these photo's of an abused 1974 nickle with similar abrasions can help, so don't shoot the messenger.
Yes, some scratchs can be so deep that there is raised metal around them that makes them look like a die break. This of dirt piled up on the side of a ditch.