The requirement for the owner's access is being generated by DB2. Top Secret for DB2 is generating a similar security check based on that. The creator for the user-defined function may need to be changed if that is found to be the case. Or perhaps there is a need to alter the procedure to change the owner.
If the stored procedures are using UDFs (User Defined Functions) under the stored procedure. DB2 documents that the owner (definer) of the function has its access checked:
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User-defined function packages and trigger packages: If a stored procedure or any application under the stored procedure invokes a user-defined function, DB2 requires only the owner (the definer), and not the invoker of the user-defined function, to have EXECUTE authority on the user-defined function package. However, the authorization ID or role of the SQL statement that invokes the user-defined function must have EXECUTE authority on the function.
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