Originally Posted by papa_lazerous
I forgot you could power them as stand alone like that, this means your wiring diagram will work fine
Not really. In stand alone mode the red wire is only connected to the Rx power wire. When connected to the OSD you have shorted the Rx power to the Expander power connection. Like you mentioned earlier I wouldn't short the two power buses. The ground wire is fine but not the power wire.
The manual states "NOTE: The Standalone Cable must not be used when connected to the eLogger!". I also think this implies that you shouldn't.