It may be possible for a blind person to see a nuclear radiation source. It all depends on the origin of their blindness, someone with no eyes or no connection of nerves to the retina could not "see" anything. They are the truly blind. Legally Blind people can often detect sources of light anyway. Legal blindness being the inability to detect objects as seen by a normally sighted person. Defined as 20/20 vision in each eye. That is the normal person can see an object at 20 feet. Legal blindness begins at 20/200 the legally blind person can see an object at twenty feet that a normally sighted person can see at 200 feet.
The legally blind person may not even have to suffer radiation poisoning to gain temporary sight, they would have to be in direct line from the radiation source. These cases have been recorded where known blind people have been in line of sight of atomic bombs and tests.
Having been treated in various ways, drugs, implants and laser therapy for a medical condition which has caused my blindness over the past 11 years I have not heard of radiation sickness causing any regaining of sight.
But being blind myself, I think if it were the case, the risks of serious harm from the radiation far outweigh any benfits.