This is a driver issue and wouldn't be related to the device itself. I'm not sure what driver you're using, but it looks like it hasn't been updated to match the new specification for the
speak() command that Hubitat introduced in 2.2.6. I would start by making sure you're using the latest version of that (assuming this is a custom driver).
You should also verify that it works if you provide only one parameter, the text to speak. This was the only required implementation of this command in the past. If that doesn't work, there may still be a problem--just a different one.
EDIT: It just occurred to me that you might be using the built-in Chromecast driver, and in that case you'd need to make sure you either upgrade to at least 2.2.6 or go back to an older version of a community app, should such a version exist, that doesn't depend on the "new" commands.