You need to read up on IQ indexes. 'Create index' defaults to the HG index ('create HG index').
IQ does not require composite indexes to cover queries. Composite indexes are primarily useful for unique keys and foreign keys. Unless you need a unique primary or alternate key to enforce RI, I would not suggest using any composite indexes in your procedure.
Instead, create the HG index on the individual columns of join columns and search arguments to start with.
As your tables come from SAP business suite, it is possible that creating a useless HG index on your tables is using too much temp to build Indexes that will not be used anyway, especially at the end of your procedure.
Chris