There is probably the fact that the Minister had known General Vance for at least a decade. If I remember correctly, they had met in 2009, when General Vance had requested that Minister Sajjan, who was a major at the time, go to Afghanistan. They served together. They were comrades-in-arms in a theatre of operations for a decade. They likely had a relatively open conversation that met the Minister's expectations and answered his questions.
In my opinion, that is the only reason that might explain why no formal action was taken at that time.