Wish I had a dollar for everytime that question comes up!
The success of your RTO business relies on the quality of the relationships you maintain with your clients, their employers, your partners, and your staff. The job of storing and maintaining those contacts and relationships belongs to your Student Management System (SMS)
You'd struggle to find any student management system that has absolutely no CRM capability, AVETMISS-compliant or not. By their very nature Student Management Systems are a specific type of CRM. It's specific in that the customers happen to be students. At the very least you need to capture a Student ID to reference their enrolment records and results, and you'd need at least a name for student certificates.
As you know, AVETMISS and SRTO 2015 take CRM requirements several steps beyond basic contact management. To be AVETMISS and SRTO 2017 compliant requires that you collect sufficient personal data to identify your students, their address details, education history, USI number, date and place of birth, language abilities, etc. That already mandates that your student management system has basic Contact Management capabilities of a CRM system.
You are required to Notify, Remind and Communicate certain information with your students. You must provide methods to deal with surveys, feedback, complaints and appeals. You must be able to report against key metrics. The NAT files themselves provide most of the statistical data needed by NCVER but also available to you. This information can be used to aid continuous improvement, business planning and decision making. These are all CRM functions and you should find them in any compliant SMS.