I think there's more here than a first glance might give you.
let's consider the facts as reported by these articles
1. As already pointed out the guy was able to just get rapefugee status without speaking Arabic at all, and being not just a German citizen but a military Lieutenant which should have shown up on cursory background check
2. there's a ~2 year span from getting the status to this incident
ergo the German government is of course lying about motive here… but this gets more interesting
3. The various articles on this subject have declared that the pistol that he was caught digging out was 7.65mm, which we can reasonably assume to be .32 ACP. .32 ACP generally speaking implies a small gun, something in the compact to subcompact size like i.ytimg.com/vi/8NdzdkaZB1c/hqdefault.jpg or files.harrispublications.com/wp-content/uploads/sites/6/2015/08/Beretta-3032-Tomcat–661x496.jpg
This isn't something you're going to be shooting up an airport with, these are guns designed for concealed carry, something that can be very easily hidden away.
Now let's think about this… why would you be retrieving this kind of pistol, hidden in an airport bathroom? The obvious thing to me is an assassination / abduction plot.
Now alright what if that's just what the government gave him and this is just a rabbit trail? Well this is where we come to the next factoid we know.
4. A 24 year old "student" in Austria was arrested in connection to this incident, and was "found" due to communication between the two, and apparently had a stockade of "illegal weapons" implied to be firearms (can you say handler).
Why arrest him if they're German state agents? No, CIA, GCHQ, or friends makes more sense with an arrest based extraction with either things having failed (with cover having been blown when he was caught getting the .32 ACP) or succeeded, and this is simply a good excuse for the German establishment to discredit Islamic terror as an issue.
Does anyone know if there were any high profile individuals that might be targets that would be passing through Vienna at that point?