Why don't try out Poly OTD service, which is free? All that you will have to do is create room resource mailboxes for all those Groups, configure those mailboxes properly and then all you have to do is add required device as a participant when scheduling Teams conference.
Group registered to calendaring service will receive invitation with Join button, that you have to press and that's all, your device should be in Teams conference. It won't get easier than that for end users.
You can see how it works on this video from Jan Zoetemelk (starting at around 12:15):