This website reported recently that Karuru was on his way back to South Africa after being released by Amakhosi at end of last season, where he found himself on the periphery of the first-team.
The 28-year-old started to train with AmaZulu on Monday last week and the club's general manager Lunga Sokhela told this website the move was imminent.
Now, according to a source close to the event, Karuru has been signed by Usuthu.
"Ovidy Karuru's deal has been done," the source tells this website.
Karuru will be the second Zimbabwe signing after Usuthu snapped up defender Steven Makatuta from his homeland side CAPS United last month.
Another player recently signed by the Durban-based outfit is Phumlani Gumede, while his brother Philani is still being assessed by the club.
Joey Antipas' side, who finished strong in the first-half of the NFD season with four wins on the spin before the festive break to slot fourth on the table, resume their league campaign away to University of Pretoria next week Saturday at TUKS Stadium.