Indeed, the King was a pragmatist, uninterested in Divine Artifacts, and very aware of his own nation's strength—he simply wished to protect his own territory.
Since there was no penalty for failure and the other party was willing to directly offer a Desert Landship, Mu You had no reason to decline the mission.
[You accepted the King's request for cooperation.]
[The King was overjoyed and immediately ordered his subordinates to prepare a banquet to host you.]
[You politely declined the King's kindness, expressing your wish to depart as soon as possible.]
...
The efficiency of this nation was quite commendable, and with no delays from the King, upon hearing that Mu You wished to act quickly, he immediately called off the banquet to begin preparations.
About an hour later, Mu You received notification: the Desert Landship prepared for him was already stationed outside the Southern City Gate.
Mu You quickly controlled his character to go and check it out.