That is actually great speed. As far as WiFi calling it is not recommended, or supported, due to the higher latency on satellite it will not work well if at all. Here is what the FAQ/Help page says:
The response provided by BirdDog is correct - Wi-Fi calling is going to be very unreliable and poor over satellite as stated on our website. Your phone provider should provide you this information as well. Please let me know if you need any further assistance.