1.Gramps sicced them on him didn't he. Test him during training to make sure he keeps his promise even under duress and then test him after to see how far he has gotten.
or
2. Gramps is off limits. Their bosses told them w/o explaining why and now they going to find out why.
You're really seeing that younger, totally vulnerable version of himself there. All of his defenses are gone and he's talking straight from the heart. This is probably the most important character moment to date.