I am willing to met good money that bear spray works on any mammal. The reason it did not work in the case was because both the bicyiclist and the wolf were moving, nor was the bicylist very close to the wolf. I am willing to bet that a clear hit has never made on the wolf. It says that he would spray towards the wolf and the wolf would back off. There is no clear indication in this story about whether a clear direct hit with the bear spray was made.
I have seen some hardcore military working dogs, and police k9s dropped like little babies with pepper spray.
Wolves and dogs in general have such keen senses of smell and I find it high unprobable that bear spray doesnt work on them, thats why it works so good on bears. In addition to the extreme pain of it entering the eyes and nasal cavity it overwhelmes the senses, which is alot to be said for bears and wolves.