You are setting @ProcedureName to Object_Name(@@ProcID) when you are in the ExecutionHistory procedure...so it's giving you that procedure name.

Pretty sure you need another input parameter added to GetExecutionHistoryStart and then pass in the Object_Name(@@ProcID)

So in your test procedure:

ALTER PROCEDURE Test

AS

DECLARE @MainID INT

DECLARE @ProcName nvarchar(128)

SET @ProcName = Object_Name(@@ProcID)

EXEC GetExecutionHistoryStart'Start', @ProcName, @MainID OUTPUT

WAITFOR DELAY '00:01:10'

EXEC GetExecutionHistoryStart 'End', @ProcName, @MainID

Sue