Trundle does not counter yorick, AT ALL!!!
His passive is totally useless. So he gets 4 hp back for 1 minion... IF he even took 1 autoattack from that same minion, he lost 35. So no matter what trundle does, he loses more than his passive makes up.
Now add to that, HOW THE HELL DOES TRUNDLE ATTACK!? That's right, he doesn't have anything to start on yorick unless he goes in totally. Unless he does, the only thing he's going to eat is W+E all day.
Sorry, just had to say that...
Chogath and Trynd are pretty good actually. They both have resource generation on death on a minion and they can keep up with yoricks minion spam. Nasus also has resource generation(Q stacks) but he can't cast as often as yorick can, and he loses valuable gold farm if he does.
Cho gets back mana and health, negating a lot of the harass, and trynd gets fury, which he can convert back into life.