Ewald von Kleist-Schmenzin did try to assassinate Hitler.
But the Award seems to be named for Ewald von Kleist.
This is Ewald von Kleist:
Nazi Field Marshall. Died in prison.
Thanks for setting the record straight (sort of). I had thought they were talking about the Generalfeldmarschall.
But, to complicate things even more, there were apparently two Ewald von Kleist-Schmenzin, father and son. The father was a plotter who talked the son into trying the hand-grenade-and-the-tunic plan. (Hitler declined to participate, so the young Lt. v. K-S survived the exercise.)
Since the younger Ewald is sometimes identified as the double hyphenated Ewald-Heinrich von Kleist-Schmenzin, the award is probably named for his executed father rather than the grenade carrier.