I have my Fios extender connected to my Verizon Router via a CAT 5 cable and it is also connected to the system via a coax cable.
The Lan Lights and COAX lights blink at first but then they go off and it is clear that the extender is not connected.
It also did not stay connected via the wireless set up method using your instructions. Has Verizon addressed this issue which seems to occur with others