Is there a way to apply an SNMP profile user permission to a custom role so the ability to manage SNMP profiles can be given to users that are  not administrators?

Any version of CAPM

No, the ability to manage SNMP profiles is only given to the Administrator role.  So even if you created a new role and applied all user permissions you still would not be able to manage SNMP profiles.  The SNMP profile user permission has a special flag that allows it to only be applied to the Administrator role