In current implementation, the counselors can view the other counselor lead details and respective activities via global search, With this feature we can restrict visibility of lead details and activities which are referred to or created by another counselor.
We can hide the details if anyone searches the lead i.e Masking of lead and disabling the edit option.
We can also Hide the recordings from the Counsellor Follow Up ( Black Bubble ) if the recording belongs to some other counsellor. Admin will be able to see all the activities but the counsellor can see activities Done by him only.
Hide Recording will be as shown in Image below :