[`Wan`] Fix VAE sampling mode in `WanVideoToVideoPipeline` (#11639)

* fix: vae sampling mode

* fix a typo

src/diffusers/pipelines/wan/pipeline_wan_video2video.py

@@ -419,12 +419,7 @@ class WanVideoToVideoPipeline(DiffusionPipeline, WanLoraLoaderMixin):
         )
 
         if latents is None:
-            if isinstance(generator, list):
-                init_latents = [
-                    retrieve_latents(self.vae.encode(video[i].unsqueeze(0)), generator[i]) for i in range(batch_size)
-                ]
-            else:
-                init_latents = [retrieve_latents(self.vae.encode(vid.unsqueeze(0)), generator) for vid in video]
+            init_latents = [retrieve_latents(self.vae.encode(vid.unsqueeze(0)), sample_mode="argmax") for vid in video]
 
             init_latents = torch.cat(init_latents, dim=0).to(dtype)
 
@@ -441,7 +436,7 @@ class WanVideoToVideoPipeline(DiffusionPipeline, WanLoraLoaderMixin):
             if hasattr(self.scheduler, "add_noise"):
                 latents = self.scheduler.add_noise(init_latents, noise, timestep)
             else:
-                latents = self.scheduelr.scale_noise(init_latents, timestep, noise)
+                latents = self.scheduler.scale_noise(init_latents, timestep, noise)
         else:
             latents = latents.to(device)