How can you split HDMI 1.4b control signals to two displays?
No, DDC cannot be split into two displays. You should at least multiplex a bus so each display can be talked to separately. But your original source must be aware of this, usually splitting of DDC is not supported.
If the TMDS is splitted, there can be no support for HDCP protection as that is for single point-to-point link only.
And HPD neither, they are both outputs from TV, they both must control their own output, regarding TMDS, DDC and CEC.
And also, connecting CEC to two displays is invalid, there cannot be two CEC masters on the bus.
You must use a special splitter chip, that has three ports, one for input, two for output, and which allows a MCU to manage DDC and HPD, perhaps HDCP too.