In Omdurman, across the river Nile, a polling official was confronted by scores of them, all with voting certificates from the local popular committee.
Mathabela has been dropped as referee of a 2006 World Cup qualifier between Sudan and Libya in Omdurman this weekend with compatriot Daniel Bennet taking over.
The cup tie was switched from Bulawayo because no hotel rooms were available for the Omdurman club as the southern Zimbabwe city is hosting an international trade fair.
The second woman to be sentenced to death by stoning in 2012, she spent two months shackled, alone with her baby, in Omdurman prison, near the capital Khartoum.
The 21st took part in what is regarded as the last great British cavalry charge, at Omdurman 45 years later - in which a young Lieutenant Winston Churchill led a troop.