Hello chroma1, I don't want to put in doubt what you say, I don't think it's true, what happens however is a mere coincidence of internet connection failure, yours or your opponent's, when it's your opponent's, you should wait a few seconds until, due to the impossibility of reconnecting, you win the game, if it's the other way around it's logical that you lose, this happens many times and FlyOrDie is oblivious to these situations.
So do not think that people do this on purpose ok, but if it happens often, you should report the situation in the option: 

https://games.flyordie.com/contactSupport.html?portal=flyordie_com&lang=en

Goodbye and have fun✌
Dav7d