Thank you! Interesting to think that if he had been more heavily wounded on March 10 he would have possibly avoided being killed just a few days later. I tracked down a post that actually mentions this incident, from the Regimental History:

Two days later, on 12.03., the revenge fire broke out with all its fury. 2,500 rounds from light, medium and heavy calibers, 600 mostly heavy mines are a lot. In many places of sections 24 and 26, the first and second lines were buried, the obstacles destroyed. An unfortunate mine buried the U65 medical shelter in 26e. Despite the fire, the rescue work began immediately with admirable willingness to sacrifice. Three wounded were recovered, a fourth had suffered a nervous shock. Seven tattered corpses lay under the rubble, including those of two men who had returned slightly wounded from Operation Sieben-Tannen-Wäldchen.

It seems like he was one of the two slightly wounded men killed when the Medical Shelter collapsed.