I blame HQ for all of this. MC had no business abandoning his mission to go help the villages in the Magic Queen's territories. If they hadn't let that random person ask for help, MC would still be fulfilling his mission of taking over the dragon army by systematically charming every person little by little. Who knows, maybe little by little he would've been able to get the dragons to feel sympathy and empathy towards weaker beings such as humans. He also would've been able to come up with excuses for the army to mobilize against the other queens. His genius idea of simply taking off came out of nowhere, and it really messed things up beyond repair.
I'm confused though. Is MC from Earth? But there are human settlements in this world too so why was Earth attacked? Also, they brought fighter planes into the other world? And the people that came from Earth have awakened skills? I think the world building needs some serious work honestly, because so far the author is relying entirely on the "feels" of the characters to get us through this tale, and honestly, "feels" in a story that focuses heavily on military elements and tactics seldom seem to be a positive.