I still think you are unlikely to get this working. There are no switches that will support this configuration.
The SWM8 or WB68 multiswitches both require four connections to the dish. Two connections carry the 99 and 101 signals, two connections carry the 103/110/119 signals. Since you are not looking at 119 you MUST use an SWM8 because of the way guide data is carried. But you need to merge and switch the 101 and 99 signals before they get to the SWM8 and that is normally done within the LNB itself, and as far as I know there are no external switches using DirecTV's technology.
Also the Ku LNBs within the Ka/Ku assemblies will still be active and you might pick up signals from other satellites which will be passed to the SWM8 in error.