Error 8/40 PLS-00364: loop index variable 'I' use is invalid
Answers originally left as comments:

Gerard H. Pille: A stored procedure can't use permissions granted via a role. You need:
GRANT EXECUTE ON RDSADMIN.RDS_FILE_UTIL TO PQP


Albert Godfrind: As an aside, granting DBA to a regular user or application is a very bad idea. It should only ever be granted to an actual DBA account.