Dude64, please use the Intel® WiDi Update Utility for PC1 and PC2. PC2 could use the latest wireless driver version 16.7.
Ellery, please check if the TV adapter manufacturer provides a manual firmware update method.
Issues with “Add a wireless display” option missing could be followed here: https://communities.intel.com/thread/46128
In order to use Intel® WiDi with 5 GHz it is necessary to use non-DFS (Dynamic Frequency Selection) channels.