I’ve reviewed 3 articles on this: the three top results on the event from a google news search for hinds county ballots. Those three articles do not back up what OP is claiming.

There are many other articles. If someone else would like to step in and do some reading and add more sourced information about this, it would be greatly appreciated.

As of now OP’s claim about Republicans’ actions in this event is unsubstantiated.

Be skeptical, people