Mboma's rise to fame on the world stage has been very rapid. This was reported only just over a year ago (my bold & italics):
LUSAKA, April 16, 2021 - In the Zambian city of Lusaka, 17-year-old Christine Mboma (born in 2003) won the All-Comers 400m race at the National Heroes Stadium in a new World Junior Record time of 49.24 seconds, breaking the previous 30 years old World Record 49.42 by the German athlete Grit Breuer from 1991 Wolrd Championships in Tokyo.
Running in Lane 1, and perhaps missing the sound of the gun, Mboma sat for an unusually long time in the blocks. When she noticed the other runners had already taken a step out of the blocks, she reacted to the start. She had many catch-ups to play up, but she steamed down the back straight to make up for the big head start she had given the rest of the field. Catching the field by around 220 meters. […]
The Namibian teenager Mboma took on her rival Beatrice Masilingi, who had defeated her in the 400m at the AGN League 5 national youth games the year before. In what was a very competitive field, the young sprinter took charge, and coming off the final curve with a huge advantage, with Beatrice finishing second place in 49.53, not too far behind. Masilingi is another talent (born in 2003). And both now are preparing for the World Junior Championships in Kenya, later in the Tokyo Olympic Games.
Last Saturday, two American athletes, Shamier Little and Quanera Hayes set the world's fastest times this year of 49,91 and 49,92 seconds respectively in Florida, but yesterday the two Namibians Mboma and Masilingi exceeded that with their performances in Lusaka meeting.
Masilingi is of course another DSD athlete. Iirc, Mboma didn't learn to use starting-blocks until a very late stage,, and actually didn’t notice the race had begun in this instance, yet the result was as reported. Mboma crushed the world record.
None of this is OK.