I'm not a coder; yeah it's difficult cause using a knife can be used not only in the begin of a round, but also to cross big distances faster, further in the round. Hard to make a bot use the knive like a human should.
Humans can think, bots can't
I've also managed the fact that T-bot with bomb arrives on bombsite empty of enemies and went into the area where he could plant the bomb, still chooses to go to the other bombsite and that CT-bots have a hard time to track a planted bomb for defuse even after all T's are dead AND enough time for defuse.