So I tried the "Universal Root De La Vega" and it broke wifi completely, it was always stuck "turning on". So I ODIN flashed the original firmware I downloaded for the URDLV process. After booting up, WIFI calling is working %100. Needless to say I'm very happy with this, and since KitKat is about to be released I'm gonna skip the root for the moment. Hope this helps someone, I know I'm not the only one that wasn't not happy with the WiFi Calling out of the box.
Note: I flashed the FW on top of the rooted FW without doing any kind of reset so I didn't lose anything. I'm also still 0x0 on knox counter.