Tvesa, multiple winner in Women's Pro Golf Tour in India, and winner in South Africa last month, shot 72-72-74 for 2-over and had three bogeys and a double between the fourth and the seventh, but she closed superbly with three birdies between 13th and 18th for a 74 and Tied-16th place.
Ridhima with 74- 73-75 was 6-over and Tied-30th.
Casandra Alexander fired a superb six-under-par 66 on Saturday to finish on 12-under-par overall and win the Absa Ladies Invitational by four strokes at Serengeti Estates.
The 24-year-old had begun the final day tied for the lead with fellow South African Kiera Floyd, but Alexander went out in 34 before a brilliant back nine saw her collect an eagle and two birdies to romp to victory.
While Floyd struggled to a 77 on Saturday and finished 11 strokes behind, Alexander's closest challenger was Spaniard Harang Lee, who also shot a 66 to finish on eight-under-par.
South Africa's Cara Gorlei also shot a 66 to finish third on five-under-par, with compatriot Stacy Bregman fourth on four-under after a 69.
