Alexa started turning on the wrong switches

I have a scene called "Bedroom lights" whose members consist of a wall switch and a lamp module, both in my main bedroom. I have Alexa linked to my EISY so I can say "Turn on bedroom lights", and it turns them on. This has worked reliably for years. Then a couple days ago I noticed with I said "Turn on bedroom lights", the Echo would chime but nothing would happen. Minutes later my wife told me the lights in the other two spare bedrooms had come on for no reason. I was able to reproduce the problem. It happened every time I said "Turn on bedroom lights".

So I went in to look at my Alexa setup in IoX (which I haven't touched in over a year) and found that there were at least a half-dozen devices in the "spoken words" list that I had no memory of adding -- including the other two spare bedrooms, and a few devices I would never want Alexa to turn on/off. I deleted all the extra nodes from the list (including bedrooms 2 and 3) and now "turn on bedroom lights" is working properly again.

My questions are:

1) How did all these extra devices get added to the list of "spokens"? Is there some automatic or hidden process that tries to "discover" more devices to add, even if I don't need them? Did Amazon do this, or Universal Devices? I haven't messed with the Alexa integration with my EISY in a long time, so maybe there's something occurring that I'm not aware of or have forgotten.

2) Why did Alexa start activating the two switches instead of the "bedroom lights" scene that it's supposed to activate? It's almost as if Alexa heard "bedroom lights" and tried to find any device that had "bedroom" in the spoken. Yet the SCENE called "bedroom lights" (an EXACT MATCH) did NOT get turned on. Which is weird.

3) In recent past I was doing some cleanup work in Admin Console and renamed all of my light switches slightly. But I did not change the scene name "Bedroom lights". And I did not think about the spokens. Did that confuse things for Alexa and cause it to turn on the wrong devices?

I'm going to have to be careful to check my spokens list occasionally - a forgotten feature.

Now my wife can stop asking why the spare bedroom lights keep coming on.

P.S. I have Alexa+ disabled on my Amazon account.