Hello there, PDMike.
The following Knowledge Base article has some great information to help with troubleshooting Facetime connectivity and Wi-Fi connectivity issues:
It seems you've covered the "Troubleshooting Facetime" portion, but feel free to review the instruction there. Additionally the "Wi-Fi Network Issues" has more great information to review:
Wi-Fi network issues
- If you encounter issues using a Wi-Fi network, use standard Wi-Fi network troubleshooting to resolve interference and other issues.
- If you are using router, firewall, or security software that restricts Internet access, verify that the ports documented in Using FaceTime behind a Firewall are open.
- FaceTime requires a broadband connection. Performance may vary according to network throughput and usage.
Thanks for reaching out to Apple Support Communities.