As of today you must use Coax to connect the STB.
Are you not able to run an ethernet cable to your Receiver and plug into your router? There are Moca bridges that you can buy that will convert ethernet to coax.
Is there a verizon set top box that also has an ethernet connection. My receiver can only connect to the internet via an ethernet connection. It does not have wifi capability.
I'm not sure what you're trying to do here. The Verizon STB connects to the ONT via coax, and the router does too unless it's connected to the ONT via ethernet (which is not usually but may be the case). If the router is connnected to the ONT via ethernet, then it must also be connected to a coax also or you do not receive guide data or VOD on the STB as these are routed through the router via IP.
You mention your "receiver" but what is it that your are trying to do?