Prince Charles Martin

1) No he isn't. His chin is questionable but he doesn't just go down, unlike Martin himself
2) Even if he was, Charles Martin is not a good enough boxer to pull the trigger on him
The blueprint for beating Joshua has existed since the amateurs. Mihai Nistor, who beat him in the European Championships, says that Joshua leaves himself too visible. But there's a world of difference between having a blueprint and executing it, and Charles Martin will never be good enough to execute it.