Ww2 3 different perspectives 3 different people meet in the end

I read this book 3 1/2 years ago and every so often I try to find it but I can’t. It starts off with an old (German? Or Russian?) police officer being called to an excavation. At the excavation they found two skeletons (1 male and 1 female) in a cavern of sorts then the rest is a flashback from the police officer. I don’t remember much but I do remember that one of the perspectives was an American tank (mechanic?). the other was the officer (as a kid) he stole a turnip from a farmer but the farmer said that the boy had to kill an enemy before he could steal from him again (I don’t think that’s exactly what the farmer said, probably not). The third perspective was a (German? Russian?) spotter for a sniper. All of the perspectives were male if that helps. The sniper was female though. In the end the sniper kills the American (after he gets redeployed?), and the kid “kills” the spotter and the sniper with a grenade. He thinks he killed them but they got to safety in a bunker, they also got trapped underground. I hope that’s comprehensive enough for people to know what I’m talking about.