I just want to add something that is important and was left unclear above.
I had contacted support to clear it up and as I thought, all free models published on CGT are by default with Royalty Free License and not with Creative Commons license.
You should trust what is written on the product page.
That point 24. in CGT terms in condition is a bit misleading and should be considered more like a recommendation - if you want to set your free model to CC license, you should switch it's license type to Custom and write that down.