As usual, I don’t quite understand what you are saying. But I think you might be saying that we can’t say that seeing "diverse effects resolve to a single result” is “collective control” unless we can show that the entities producing the diverse effects are control systems. If you do this analysis I think you’ll find that some of the most interesting cases of what might appear to be collective control do not involve any control systems at all. An example of such a phenomenon is spontaneous synchronization (SS).
There are actually many different examples of SS, all of which are lovely examples of diverse effects resolving to a single result. Several examples of SS are described in this video. Some of these could be called collective control but others are simply results that are produced by a collective of causal systems; perhaps they should be called examples of collective causality. I suggest you watch the video and see if you can tell which phenomena are examples of collective control and which are examples of collective causality.
I, therefore, propose that your definition of collective control as "a phenomenon where diverse effects resolve to a single result” be augmented to read "a phenomenon where diverse effects produced by a set of control systems resolve to a single result”, and that we use your definition of collective control as the definition collective causality.