In any case he needs roaming and holding up the ball ticked, I'd tick run from ball to sometimes as well personally.
Another problem you have could be that him and Forlan are similar types of player, Cavani should be the more advanced of the 2 but not as advanced as a poacher is.
he's obviously best as an advanced forward. definitely NOT a target man. Having him just sit on the last defender and break is not his game. Haven't you watched him irl?
try playing Snjeider as advanced playmaker attack and you can have two advanced forwards
The answer to the original question is calm down, he's just signed for a new team, 7 goals and 4 assists isn't that bad, especially if Forlan has scored a few. You do need to play to his strengths, but let him settle into the team and he'll be fine
The problem with poacher is that he has "comes deep to get ball" as a PPM. Those two don't work very well together unless you tweak a lot of the settings.....the poacher settings don't let him do much with the ball when he comes deep. Plus, Cavani has huge work rate and stamina, where the poacher wants to just sit there.