It is not possible to exclude devices from system collection or polling jobs. However, you can disable the system collection job, then create an ad hoc Sync Archive job to collection configs from all of the desired devices.
To do this so that the list of devices collected is dynamic, go to RME > Config Mgmt > Archive Mgmt > Sync Archive, and click the radio button "Group Selector". Then, select the device groups for which you want configs to be archived. As new devices are added to those groups, they will have their configs automatically collected. Finally, select the other desired options, and schedule the job to run periodically.