I've read the docs about setting up the echo with the Echo Skill. Some of the wording left me confused about whether the hubitat can fully control matter devices paired with the echo or whether ther are limitations. I'm new at this. If someone could expand on the subject a bit it would be a big help. I don't use the echo for anything right now so it's only purpose would be to act as my matter controller. It would sit in a closet and never be looked at or talked to.
What I've done is use my Amazon Echo (Show 5") only to initially onboard my Matter (non-thread) devices via the Alexa app. I then followed the Hubitat directions on how to use the Alexa app to provide a commissioning code to directly add the Matter device to Hubitat. After that, I removed the Matter device from the Echo (since I don't need it there). At this point, my few Matter devices are just directly talking to my Hubitat hub.
Either you read the wrong docs or mentioned the wrong ones here. The Hubitat Amazon Echo Skill, as the docs mention, is for integrating Hubitat devices into the Alexa ecosystem. It does nothing for the other way around; nothing really can (or at least almost nothing can), considering Amazon does not provide a way to get things out.
The "almost" above is because of Matter. If you have a Matter device paired to your Amazon Echo, you can use the Alexa app to put it in pairing mode and then also add it to Hubitat as a Matter device. Again, this only works for Matter devices (it will not do anything about arbitrary devices you have paired to to Alexa).