Amazon Echo with Verizon Fios issues

I have verizon fios and I am using my own Enterprise Firewall connected to the ONT's ethernet port. After that I have the FIOS gateway's wan port connected to my firewall. All of my amazon echos and TV units are connected to the fios gateway. As long as my Firewall is first in line I cannot change channels with Amazon Echo but if the Fios Gateway is connected to the ONT I can change channels.

I don't understand why the FIOS gateway has to be connected to the ONT in order for Amazon Echo to change the channels? Are there any ports that need to be open for this to work? Any help would be appreaciated.