In the last few weeks, I re-installed my Google Chrome Cast (first Gen) to my TV, and thus to my Harmony Hub. I can "change" to Chrome Cast. but I cannot launch it independently for some reason, by voice command. I will preface this by adding that I use YONOMI app to help interface with the Harmony Hub As well. I don't know how much it helps or slows things ir speeds things, but I know from setting up systems, that it will allow control of a second Harmony Hub. It was recommended for THAT system installation due to the multiple hubs.
I can command "Alexa, Turn on fire TV" and she does that, but when I try "Alexa, turn on Chrome Cast" or any variant of chrome commands I get a "Sorry, I didn't find Chomecast"... most times.
Once the Fire TV is on, I can command "Alexa, Turn on Chromecast" and the devices work together to change to Chromecast.
If Chromecast was the last thing I had "on" I will sometimes get a direct response of Turning on Chromecast from what I consider Scratch... Sometimes I get the "Sorry I didn't find Chromecast" response... Very hit or miss.
This is the only item in my entertainment system that gives me trouble... and to add one last thing to this same issue, Sometimes when I do change to Chromecast with Fire TV already on, by using the above command that actually works. Alexa says something about a secondary hub... Sometimes it doesn't. Again, very hit or miss.
Now... If I start from scratch and command "Alexa, Tell Harmony to turn on Chromecast" it seems to work every time.
I think the grand issue with all features related to Harmony hub and Alexas, is the fact that you cannot summon Status of the equipment. Maybe one day IR remotes will be a thing of the past and RF or WIFI will be the norm. Some components nowadays can communicate via wifi or bluetooth, and can actually relay their status to the controller through one of the wireless features. I seek future purchases to help me eliminate any IR devices going forward. My next TV will likely be a WIFI enabled TV that either already has some form voice control, or will integrate with my AI devices through WIFI. Bluetooth is too sketchy for this stuff in my opinion, with latency issues that are always difficult or expensive to get around. Anyway... I thought I'd throw in some more Harmony Hub input. It probably won't help, but gives some insight into common issues that can be had.