Electromagnetic repulsion is the reason why the fragments have the velocity in the first place. They are moving away from each other.
Sorry, but this simply isn't true. The energy comes from the mass difference due to the fission of the isotope, nothing else. There is no guarantee, even, that the two particles have the same sign of charge, depending on which one gets more or less of the original fissioned atom's electrons.
Look dude, my PhD minor subject area was Nuclear Science, this is kindergarten type nuclear knowledge.