The linked interview has one(!) offhand comment by Abram de Swaan about the alleged practise. The interview is in part to promote his book “The Killing Compartments: The Mentality of Mass Murder.” which of course features Nazi Germany quite a bit. So I went ahead and downloaded said book. The words ‘dog’, ‘puppy’ ,or ‘pet’ are mentioned zero times in the entirety of the book.
Trying to find the book and more sources for the allegation I came up with nothing else.
While “SS-Troops” (idiotic generalisation in this case) like the SS-Totenkopfverbände did many fucked up thinks and would be fucked up enough to feature the alleged dog killings in their training - there is so far no proof whatsoever.
If this were the case it would be in every other movie about WW2. It’s in Kingsmen FFS, where the good guys do this as part of their training.