Confirming I just installed IE11.0.9600.16428 and I can see Enterprise Mode now, so the reg settings I did earlier are working now. Also confirming I copied the inetres.admx\adml files from the PC with IE11 to domain GPO central store and now I see the "let users turn on and use Enterprise Mode...
I'm using Windows 7, the opening line (and other pages) suggests it can be enabled on IE11 on Windows 7, "Enterprise Mode, a compatibility mode that runs on Internet Explorer 11 on Windows 8.1 Update and Windows 7 devices". I think the IE11 I have installed is an old version, it even says...
setting not in group policy
I assume you need to copy a new admx file into the GP central store to get IE11 settings? I don't see any Enterprise Mode settings in our GP. I haven't seen it mentioned in any Enterprise Mode guides I've looked at.