Yes, all devices are using the same authenticated user with SG.
Here’s more scenarios that we tried.
Device A creates Doc, Device B and C syncs and gets this Doc
Device A updates the Doc, Device B and C is offline and does not grab this revision
Device A deletes the Doc, Device B and C comes online, both Device deletes Doc
Device A creates Doc (Rev1), Device B and C syncs and gets this Doc (Rev1)
Device A updates the Doc (Rev2), Device B comes online and Syncs this Doc (Rev2). Device C is still offline
Device A updates the Doc (Rev3) again, Device B is online, syncs and Doc (Rev3) is up to date. Device C comes online too and the Doc (Rev3) on Device C gets up to date.
Device A deletes the Doc. Doc is deleted on Device B but on Device C, Doc gets reverted back to (Rev1)
From what we observe, if the devices are up to date with every revision, the document will sync correctly even when it is deleted in the end. But if a device misses one revision and the document is deleted, the document reverts back to the last revision that was available on that particular device.