How do you know, for example, that the tethers do not move upwards naturally because that is the shape they want to adopt because of the materials they are made of? Deprived of external forces like gravity, flexible objects will adopt their lowest energy shape, i.e. one with the least tension and compression in them. You seem to be expecting them to simply adopt whatever shape they are put in and stay there.
I just redid the wiring behind my computers while installing a KVM switch...stiff cables sprawling every which way, even under a full 1
g. They've got a bulky, heavily protected umbilical carrying air, power, and electrical signals...and it's something they *want* to be a bit stiff, so it can be more easily manipulated in freefall without flopping around and snagging on everything.
As pointed out earlier, achieving neutral buoyancy is not difficult, some unobtrusive weights would have done the job perfectly well, and just positioning the camera above or below the set would cause buoyancy errors to be far less obvious. Blue tinted water could trivially be compensated for by using lights with low color temperature, or in post processing.
So, we have a country that has demonstrated all the capabilities required unnecessarily and riskily deciding to fake the EVA, and failing to compensate for some obvious giveaways while doing so, or we have an EVA with a stiff tether doing what tethers have been observed to do in other EVAs, and a camera with poor color balance, as is fairly typical, color balance not being a great priority in their application. The color balance is even off in the expected manner of a camera attempting to automatically compensate for a color cast in the scene, lit partially by the big, bright blue Earth in the background.
Summary:
zero evidence of a hoax. And the video does in fact provide evidence of a freefall, airless environment not reproducible on Earth. Radars around the world track the launches, amateurs observe them and photograph them with their scopes, and we ourselves did similar operations decades ago with far more primitive technology. So why would anyone believe it was hoaxed?