I don't know if anyone has pointed this out...but that scan of Kraven vs. Black Panther is Alyosha...Not Sergei.
Which one? The one Where BP wins? Or loses?
The only fight between T'Challa and Sergei was laced with factors and didn't have a winner. The fight where Kraven beats Black Panther in the kitchen, and then Black Panther stands over Kraven in front of the Avengers, are both Kraven's son, Alyosha.