Good question - I worked at the ASDEX Upgrade (AUG), also operated by the IPP but a tokamak instead of a stellarator: At AUG similar images and videos [0] are recorded by IR cameras. These cameras require strong cooling and a magnetic / electric shielding as described in [1]. Per plasma discharge (~10s) around ~8GB of video data is recorded. There are also fast frame cameras for dust tracking [2] and similar things. I assume the same techniques are applied at Wendelstein.
The 3+1 dimensional spacetime is not embedded in a higher dimensional space [1]. If there are additional dimensions, they have to be "rolled up" and tiny.
[1] https://vitalik.ca/general/2021/01/11/recovery.html