hi
You NDMPCOPYed it from path like /vol/vol_name_/qtree/lun.lun ("live" file system) ? or from /vol/vol_name_/.snapshot/snapshot_name/qtree/lun.lun (snapshot)?
As for the convention. i don't have a system here with SMSQL to check if the naming could be legit for consistent SMSQL backup behind a snapvault.
From what i can see in the docs. the only way to integrate SMSQL with snapvault is via DFM. did you had it in the organisation ? is that server still alive and can show the job that created that snapshot?
https://library.netapp.com/ecmdocs/ECMP1217281/html/GUID-C89B2358-05FC-4C4A-94D6-A0480F65D072.html
because. the name you have dosen't look like the names my DFM generating (either in format of "2018-03-25_2334+0100_daily_DS_" or the original snapshot name) i tend to think what you have there is very likely non-consistent snapshot from independent scheduled snapvault.
is this volume still have it's snapvault config? (command: "snapvault snap sched"). if that matches to your snapshot name. we can very likely assume you have a non consistent one..
Gidi