I think that it is either a fake, or possibly a mistake or misunderstanding.
Geiger counters are readily available, I would expect any high school science department to have one. Universities that teach science subjects probably have dozens.
A significant minority of ordinary citizens have geiger counters.

Has anyone else reported a large increase in radiation ?
Not so far as I am aware.
TPTB could not keep it a secret, it is too easy to take independant measurements.
A power reactor meltdown would be a large scale disaster that could not be concealed without the closure of large areas of land, hundreds of square miles.
Is anyone aware of any such closures ?

There would be hundreds, perhaps thousands of witnesses to the accident. Could the government really silence every single one ?
Even if they killed every witness, I think people would notice the sudden and unexplained disappearence of so many.