Yes but illumination is not the problem here. The robots have no problem with lighting. Imaging is a problem. Your search for "refractive elements that would

Yes but illumination is not the problem here. The robots have no problem with lighting. Imaging is a problem. Your search for "refractive elements that would work in the high radiation environment" would likely lead you to something like the optics that Toshiba has developed for these robots. Remember to also account for the thermal effects; radiation of this magnitude is capable of heating the internal elements of your assembly by hundreds of degrees, and your telescope-like camera must maintain its tolerances very precisely to produce a usable image. And perhaps the hardest problem of all: how to maneuver all of this stuff into place through hundreds of meters of industrial hell, where humans can't even stay long in the parking lot outside of a shielded truck. Tackle these problems using no robotics, and you'll be famous, I guarantee it :)