"We want to see the ship, Shumin, while undergoing maintenance [at a dock], so come to us". As paraphrased it strikes me as odd/weird such a royal request was not corrected before being issued - either they come to the dock (the workers are here), or wait until done. Flying out to planet Diamond should be understood as impossible, or at best incomplete and the has to fly back to complete the maintenance, which likely would make Nao miss the deadline.