If khan picks firing line, he can make all of his teammates in a radius immune to stuns. That renders grumpy bomb and poppy bomb useless. However, this means that you can force him to use battle shout with grumpy bomb.
Torvald is a sitting duck. If he's on the point, either rain down sticky bombs, drop grumpy bomb or poppy bomb him away. He has no movement abilities. As long as you have the high ground, he's toasted.
Sha Lin is at heart a sniper. Eye him from a distance and try to come closer without him noticing. Then, jump at him with poppy bomb while firing sticky bombs. If you get the jump on him you will kill him.