Did you even bother to read whole wiki page you give link for? It's really short and this is interesting part :
Grammar problem[edit]
In
German grammar, a
compound noun is always a single word, so using two words "Teufel Hunden" is grammatically incorrect. The correct German would be
Teufelshundein
nominative,
genitive, and
accusative cases, and
Teufelshunden only in the
dative. In either form, the linking element "s" steps between the words. Examples:
Sie waren Teufelshunde. – They were Devil Dogs.
Er war ein Teufelshund. – He was a Devil Dog.
Er sprach von den Teufelshunden. – He talked about the Devil Dogs.
Furthermore, the word "Teufelshund", though not unknown in the German language, is rare, and this use may possibly be an example of
Denglisch. The more common equivalent is "Höllenhund" ("dog of hell" or "
hellhound"), the German translation of the mythical
Kerberos.
So ... NO ., No German speaking soldier would never say "Teufel Hunden" . Sorry mate, not true story. I'm not saying that some marines are not very good soldiers. Many of them are, but definitely not all of them. Simple because there's too many of them. I know that is nice myth to be told to new Marines, but simple doesn't sound true at all.
Most of heroes are dead. Some of them survived because they got really, really lucky. So... yes Camarón, Dien Bien Phu, etc, etc. Sorry mate, but I simple can't view whole USMC as some super soldiers, all-hero bunch of men (and women). I'm not doing that even for FFL.
Simple question to you. Did USMC anytime in history give such praising nickname to their enemy as Devil Dogs are?