Well it seems Din is jumping to some sort of conclusions here at that initial reaction, but she's not going to try and correct him. After all, she doesn't know enough to dispute any of it. She doesn't know why the Jedi sent him back. There could be a whole host of reasons. Though she doubts it was because Grogu wasn't good enough. She's seen what that kid can do.

But that last part seems to calm Din down at least.

"Yes, you should have," she agrees. Though she can't blame him for doing what he thought was best for Grogu. Fate simply had other ideas apparently.