Workflow error - Method {cbbMethods} does not exist on SmartObject

Hi,

I'm getting the error below from a K2 workflow.

However, the selected method (Execute) does exist in the target SmartObject. Below are screenshots of the workflow settings and the SmartObject method.

Any ideas on how to solve this? For additional context, this was also copied using the package and deploy tool from another environment where it works without any errors.