I wouldn’t say they both serve the same purpose. Guardian barely mentions the tadpoles in comparison, there’s no negative consequences, and it’s much less directly tempting. Daisy was mysterious, manipulative, and had an otherworldly feeling of both dread and hope about her whereas the guardian is just whiny and sits in your ear begging you not to do any little thing they disagree with. Also with the song between the lyrics about fusing together, the weird distorted sounding words in the middle, and the last line about just leaving you dreaming by the river it’s clear none of that would relate to the guardian.