You're mostly right. Red can do stills.

http://nofilmschool.com/2015/07/red-epic-scarlet-6-0-23-firmware-stills-...

Tokina makes the 11-16mm in a declicked option in EF.

These cameras are so lost on me. They made an ENG style studio camera but its micro four thirds. There are no m4/3 lenses that are ENG style. Can't put a B4 ENG lens on it because the sensor is too big. I just don't understand....

They currently have Canon C500s up there. They last a few months before the sensor is destroyed from radiation. Then they send the bodies and hard drives down. They have also converted the C500s to work with the old Canon batteries found in the old camcorder units. This was to save a lot of time and money because they would have to run tests to make sure the newer batteries wouldn't explode or have any other issues in space. So since the old Canon batteries were approved, they used them. Now all of this applies to the NASA IMAX footage. I'm not sure if that would ever be available like this in public domain but this all comes from the DoP that trains the astronauts, James Neihouse. All this to say, theres a lot more than what you think that goes into the thought process and choices for what cameras and gear go up there. I can't remember if they tested the GH4s but they ran hard tests on a lot of different cameras and some would not hold out long enough due to the radiation as others. So they chose Red and the C500.