I suspect you are missing some points. Semenya came from an area know to have higher than normal DSD prevalence. This has been discussed in articles and I believe why Ekkart Arbeit travelled to the region to seek athletes with this DSD.
Plus do you think that the lack of menstruation and the effects of a testosterone puberty were not picked up by the health professionals at the time?
You can believe that Semenya did not know, others disagree. And as pp has stated, and this thread has discussed, when Semenya found out they could have respected the fact they were male and started running in the male competition. Instead, they chose to continue to compete in the female category because by then, they could legally.
Do you support Semenya’s decision to keep competing as a female knowing they were male ? Do you have compassion for the female athletes Semenya has repeatedly told to get over their loss and that they didn’t try hard enough?
Other male athletes with DSDs have chosen to not compete as females when they could have taken advantage of this. Semenya made their choice with full information.