These additional statuses are documented here:
https://global.download.synology.com/download/Document/Software/DeveloperGuide/Firmware/DSM/All/enu/Synology_DiskStation_MIB_Guide.pdf
* DataScrubbing (13): RAID is DataScrubbing
* RaidDeploying (14): RAID is deploying Single volume on pool
* RaidUnDeploying (15): RAID is not deploying Single volume on pool
* RaidMountCache (16): RAID is mounting SSD cache
* RaidUnmountCache (17): RAID is not mounting SSD cache
* RaidExpandingUnfinishedSHR (18): RAID continue expanding SHR if interrupted
* RaidConvertSHRToPool (19): RAID is converting Single volume on SHR to
multiple volume on SHR
* RaidMigrateSHR1ToSHR2 (20): RAID is migrating SHR1 to SHR2
* RaidUnknownStatus (21): RAID status is not included in the status above