I managed to fix it, by some odd way. I think I made all the displays extended, put 2 to middle and made it the prefered display, then I created the group.
Thank you! I Can confirm that this solution works.
I've spent a couple of hours fiddling with eyefinity groups and stuff, and it works every time the group is created from the 2nd monitor.
It doesn't have to be the primary or the center one, the important thing is that you select the drop down on the 2nd monitor under "Creating and arranging desktops" in CCC and from there select "Create group".
This should get you an eyefinity group with id 2, and then it just works.
Also I can recommend using the campaign to check if it works, the "Follow" HUD text can be seen if it's working ( when applicable ofc ).
There is a quirk with this though, if you use Win + P to switch to eyefinity there's no guarantee that you will get the same id on the group as when you first created it.
Tried using CCC presets but that didn't seem to help either.