A couple of Danish articles where historians discuss fact and fiction. I don’t know if a Google translation will render them readable, but feel free to ask if anything sounds too weird:
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Under Sandet - Sandt eller falskt?
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Interesting points;
"In May 1945 there were no authorities in Denmark. The handful of British soldiers who had come to the country to take control of the German occupation troops could not solve the task at all."
(Point of interest, my father, during his national service, was based in Northern Germany his regiment was tasked to assist defend Denmark in case of Soviet attack)
"In reality, the German military force was still the only organization in Denmark that at this time was able to solve such an extensive task as clearing the many mines on the West Coast."
"...former German commander in Denmark, General Lindemann, who subsequently ordered orders for German engineers who had been coming home to return to their barracks to be available as miners"
"In the world of reality, his task would have been a German commander who had probably served for a long time with his men."
"And far from all the German miners were defenseless boys. There were also many tanned veterans among them. It was a typical average of the German military force in 1945. A few experienced soldiers who had survived years of war, supplemented with school boys and men of retirement age who had been summoned in Nazi's last convictions"
"Of course, it would have been desirable to equip the soldiers with mining detectors and other special equipment, but these were rarities even in the warring armies of that time and even more in a country like Denmark"
"One can discuss who was ultimately responsible for the German soldiers being put to clean mines. Was it the Allied Military Commission that brought the proposal? Was it the Danish politicians who thanked yes? Or was it German general Lindemann who issued an order whose validity is doubtful?"
"Everyone thought it was reasonable that the Germans cleaned up, "turning the blind eye. In men's eyes, the Germans had no rights and could not expect mercy in the first months of the war."
So, from that article, we are not sure where the plan to use Germans came from, but the German commander approved it and it was mainly a German run operation.