In the end, Miro did make a cake for Arya before their return.
The other three watched as Arya ate the cake happily like a child and there was some incomprehension on their faces.
But no one said anything.
No matter what… this underage girl is still their superior.
…
Once the assessment mission was over, they all went back to Sea Country Base through their own methods.
It was a vacation time and they didn't have to stay together at all times.
Or rather, Arya could go back earlier while the other three had to stay together and monitor each other on their return. She also kindly gave Riley and Taurus a mission that they could complete together.
As for the reasons why Arya came back earlier…
"Do I really have to enter the laboratory again?" Arya asked, her tone contained traces of displeasure. She thought that there was a solo mission that she had to do again, but it was actually a call to the laboratory?
