If the split was a week old and queenless you should not have see aggression toward the caged queen.
This could be an indication that a queen was transferred to the split by accident,
( been there done that). Look for eggs if the split was without a queen for seven days you should not see any eggs as they hatch into larva in three days. If you do see eggs you either have a nice store bought queen doing her job, or a different queen laying. Then do a good inspection to find one with a painted dot on her. If you find a queen unmarked check the hive that you made the split form for queen cells.
The Busy Bee teaches two lessons: One is not to be idle and the other is not to get stung.