SAN snapshots, and I don’t care who your vendor is, by definition depend on the production LUN. We’ll that’s the production data.
That’s it. That’s all I’ve got. If that production LUN fails for some reason, or becomes corrupt (which sort of happens a lot) then the snapshot is also corrupt. And if the snapshot is corrupt, then your backup is corrupt. Then it’s game over.
SAN snapshots are a good part of an infrastructure-side recovery plan, but databases have their own recovery time and recovery point objectives. Conflating these two can lead to sadness.