So with all due respect what has the German Aerospace Center (DLR) launched into space since the V2 that makes them experts on human spaceflight? Passengers on the Space Shuttle? Built a structure for a soft landing probe that crashed into a comet?
When they finish whatever ground testing or re-design NASA feels is needed launch another mission with supplies. If the spacecraft makes it to the ISS without any issues bring the two astronauts home on that craft as it it show it can re-entry without a problem. If all that happens then NASA...
Were there any issues with the uncrewed return flight? If they can't figure out a ground test that NASA will accept then there is going to have to be another uncrewed test flight but who will pay for it? The biggest problem that I see is that NASA is going to have to grow a pair before...
I don't see the ISS as a closed system. Without frequent resupply any habitat therein would soon expire.
As for the earth, yes it is a spaceship and we are, in Zefram Cochran's words "all astronauts on some kind of star trek.
So is it really a spacewalk if the astronaut just stands in the hatch? Just more a test of the suit. Reminds me of the Apollo 9 mission where the astronauts stood in the hatches of the command module and LEM.