I see what you mean, but he most definitely got tricked. Anderson lulled him into going jab for jab, Okami could have tried to get Anderson to kick, could have tried weighing him down but went with the worst strategy of standing right in front of Anderson. Sure the knees probably sucked, but a smart fighter would have known to keep trying instead of trying to stand flatfooted and boxing with him.
But technical boxing is what Okami is best at in his striking, so that's what he went for. I guess he just couldn't do otherwise. He was sort of in survival mode without being rocked. You might underestimate the power of Silva's knees. Silva doesn't look so powerfull, because he is so lanky, not really ripped and his movements look to have this rather soft fluidity instead of brute crispness, but his perfect technique makes it more damaging than from most of the other fighters.