There are several issues in your input file.
First, you left an EVENTDAT card inside, conflicting with the output unit (22) of the suggested EVENTBIN card.
Then, in the latter, you asked to score in your DETECTOR region three times.
(Also, there is no point in limiting the scoring to EM-ENRGY, what I meant in my previous post is that the deposited ENERGY will come from electromagnetic particles originated by the isotope decay).
Avoid unjustified biasing and threshold adjustment in the RADDECAY card, which you should just use to activate semi-analogue decay.
You selected in BEAMPOS a volumetric distribution for your radioactive source, over a sphere of 1 mm radius, so I do not see the point for the annular request in the BEAM card, where in addition the isotropic choice is meaningless for an ISOTOPE, which is at rest.
The produced EVENTBIN output will be a human readable sequence of energy deposition values [GeV] in your detector, such as
that is available for any kind of analysis of your own (including spectrum generation), with no need for FLUKA user routines.
Take care