Checked in game, the pet health is very low, at most 9. As evidenced above from an in era source and collaborated shortly after its max health should be in the realm of 100-150.
As we can see here, the pet shouldn't be getting insta killed by low level damage shields.
I feel this is corroborated by a later post, which acknowledges the pet is mainly a toy, but also insinuates the pet can stand up to the wizard DS which is cast on most frogs in Seb:
As it stands the pet doesn't really have a shot to do anything more than one underpowered hit to anything with even a basic DS, let alone 700+ damage to something returning 2dmg/hit.
Edit: further evidence xuzl pet should have 100+ hp