Oh, you're going there in the winter!
Killer Whales are usually observed in the spring and summer season, between April and July.
The season will slightly differ depending on the year though.
The Killer Whales won't be around Rausu in the winter, due to the drift ice.
There's a lot of interesting wildlife in rausu area in gthe winter too.
I can recommend you to a local guide who I met last year, so please message me if you need.