I found a discrepency in the rulebook on silhouette, and was after some clarification.

Table 6.3 on page 265 lists 'children, large dogs and goblins' as being examples of silhouette 1.

The sidebar on page 326 next to the entry for dogs lists small dogs as being silhouette 1, and large dogs as being silhouette 2.

Given that a wolf is likely of similar size to a large dog, it's silhouette is...

???

..practically meaningless.

As I was researching the answer to your question, I actually found out that Japan had two types of wolves during the feudal era. One type only got up to about 25 lbs., meaning that it should probably have a silhouette 1. The other type seems to have gotten to 100lbs or maybe slightly over, which would make it silhouette 2. Rokugan isn't japan, but it could be possible for both answers to be true in Rokugan as it would have been in japan.

I would also say that the average rokugani would probably consider a dog of 25 lbs. to be "large", even though it's still silhouette 1. I strongly suspect that the Rokugani barely consider wolves to be dogs.. and Moto war-dogs are probably hated by other clans as well, which may lead to a general rokugani belief that the bigger (silhouette 2) breeds of dogs are not actually dogs, but are instead beasts. In this way, the difference in the silhouettes listed might be a matter of perspective.