Vis touched the sapper?

(NO SPOILERS PLEASE!) I’m currently at page 42. But I need some help. When he’s at the orphanage and Hospius is there. Why is it a problem that he saw vis touch the sapper?

Could someone explain???

(NO SPOILERS PLEASE!) I’m currently at page 42. But I need some help. When he’s at the orphanage and Hospius is there. Why is it a problem that he saw vis touch the sapper?

Could someone explain???