If getNodes() is called in a containerized setup, it tries to lookup a legacy cluster and fails, because there is no environment.

If the target was hthor, the correct answer is always 1.
If the target was thor, then in most contexts, it will execute in Thor context and will get the correct answer (# slaves).
But if the target was thor and it is executing code outside of Thor at the time, then it is unclear what the answer should be (it used to be the size of the cluster you submitted to).