The HTTP page from the REST WS load all the methods but for some reason, SOAP UI or any other Web services utility, only show the rest_access method.
The option @NX_REST_WEBSERVICE_RESOURCES_TO_EXPOSE was installed only with the value "rest_access" which reduced the list of REST web services that can be used to "rest_access".
Service Desk 14.1 or higher
1. Log in SD with an administrator account.
2. Go to the administration tab->options manager->Web Services->REST_WEBSERVICE_RESOURCES_TO_EXPOSE .
3. Click on it and uninstall it, then the SD services need to be restarted.
4. Once the SD server is restarted test with SOAP UI.