Your DAG (Dynamit Actiengesellschaft) 9mm blank looks to me, in the picture, as if it has an olive drab-colored bullet. If so, it is specially for the Uzi SMG, which was used by the German Bundeswehr for some time (don’t know if it is still standard in that service or not). It is commercial index number 212 8322. If with a black bullet, it is primarily for the Heckler & Koch MP5, commercial index number 212 8284. I don’t know exactly why two different blanks were necessary. The ones with Olive Drab-colored bullets have a slightly longer over-all cartridge length than the black-bulleted ones, so it may have something to do with feeding, or proper fit to the magazines. I simply don’t know, and have never received a straight answer, even from DAG reps.
The IMI dummy blank could be a legitimate dummy made up for trade show displays, or even a box-maker’s dummy (dummy rounds sent to the box makers to insure proper fit when they manufacture packaging for the rounds). It probably is not a training blank of any kind, although that is not impossible. It is hard to say. Dummy blanks are not unknown - I have 8 or 9 in my collection. I have a blank about identical to yours except the date on it is “91”. You don’t mention whether your round has a flash hole in the primer pocket or not. Mine does not. I have seen the one I have in other collections, so evidently some quantity of them came into the USA. It is not impossible that it is simply a dummy round based on the blank case, but used in place of a dummy ball round for the same purpose. Again, I don’t know for sure.
The WRA 9M-M round was a military contract, probably for a foreign country, during WWII. It is possible that American special ops (OSS, etc.) people used these also, but most of this ammo seemed to go to England or China. Some may have gone to underground partisan units in Europe, also. I have a 50 round box and a 64 round box that were for England (or the United Kingdom in general) and the rounds don’t have the four segment primer crimp. Only my Chinese contract box, printed in the Chinese language, had rounds with this crimp. That is NOT a definitive statement that no one else got rounds with this crimp. It is only an explanation of what I can prove from my own collection.