Which device does iTunes Match use as its source?
When you enable iCloud Music Library in any iTunes library the music content in that library is compared with your existing iCloud Music Library held on Apple's servers, and the two are merged. When you first subscribe the initial contents will include all of your unhidden purchased music. See Identify cloud status icons in your music library on your Mac or PC - Apple Support. Those items that are marked as purchased, matched, or uploaded, will be visible in all iCloud Music Library enabled iTunes libraries and devices. Tracks that are marked as duplicate, error, removed, etc. are only in the local library until you resolve their respective issues. Tracks marked as waiting and are stored locally should complete the matching/upload process if you use File > Library > Update iCloud Music Library. Ideally you want at least one library where everything is download and stored locally rather than in the cloud, and that library should also be backed up.
tt2