It's general policy to not comment on items that have not been released yet. Frost Atronach crates and their contents have not been officially confirmed yet, nor has the atronach target dummy been confirmed as being a crate reward. UESP's page is a work in progress and is subject to change.
That said, the Frost's datamined text suggests "This construct is equivalent to an exceptionally hardy veteran dungeon boss." Again, subject to change, but Frost is most likely not a trial-level dummy.