It all depends on what he did in the military.What was his post,what was his rank,it all makes difference.Even though Germany and Canada have a good relationship it has nothing to do with his military post.The reason it takes a bit longer is getting the clearence to his military files.
Canada has to put in a request to the military where ever it is, get the clearence then have the files transfered to the visa office,where they hand them over to the company doing the background checks so it all depends on how fast the files are cleared and transfered.