I believe that the comunists did discover’s Genghis Khan’s tomb, but they destroyed it or at least permanently sealed and hide It to avoid a nationalist uprisinga in Mongolia/Inner Mongolia. Russia and China migth be hiding it to this day.

They got all the reasons to. The Soviets Wanted to maintain Mongolia in their sphere so hard they banned even the mention of Genghis Khan in books or mentioning his name. Plus, they wanted to keep controll of of Tuva and Buryatia (they still do). China wants to keep a strong leash in Inner Mongolia.