I think it has to be something about the hosting, I use shared hosting, if version 3.0.9 works for you and it doesn't work for the rest of us, it must be something about the hosting, it has happened to me with other themes that I have been testing and to other users other hosting did not work for them.
Let's see in future versions if there is more luck, this theme has many requirements for its operation.
I have tried Booking Core and practically does the same or better and works very fast and well. If Traveler doesn´t work for you, try Booking Core, you will not be disappinted.
Booking Core - Ultimate Booking System | Babiato Forums
Thank you very much to all of you who make Babiato great.
Greetings.