@TheDragonOfFlame More random things about Forebearers pact.
Note that the Guardian Spirit statblock doesn't preclude most actions. Unless I'm missing something, it can still take the Use an Item action, for instance - a property "cannot take actions other than the Helpful Spirit action," or just "Can only take dodge/disengage/etc actions" would fix it.
I don't know if Ancestral Horde is supposed to make someone un-rezzable by "destroying their soul" - a true permadeath, as far as I know, isn't something that a PC can easily accomplish. You could go with "the creature's soul is defeated" if…