Failure to create contact point when creating iSupport SR

We have had a number of users say that some of their iSupports are not visible in the View SRs option.  We eventually diagnosed that the invisible records did not have the "Contact Type" fields completed. We have just under 600,000 iSupports on the system, and 268 of them do not have a related record on table CS_HZ_SR_CONTACT_POINTS.  12 of them were created before June 2011; there's then an almost 5-year gap until March 2016 (when we applied a CRM patch to our system), since when there has been a steady flow of 7 or 8 a month where this