Not on DCL. On other lines where the service charge is mandatory. The service charge is pooled to be shared by more than just those crew members you deal directly with (room host/dining team), like the laundry & kitchen staff.
Yes, if you tip directly to, say, your dining room server, that tip must be handed in. Once the determination has been made that you have not removed the service charge, they additional tip will be returned to the person who you gave it to. If you've removed the daily service charge, the "additional" tip you gave will be put in the pool to be shared. Meaning that the person who you've given the extra to is actually getting less.
On Princess, the daily service charge is pooled across the fleet to be shared.