[V5, page 211]: "Only draining a human of blood, thereby killing them, can reduce Hunger to 0."
RAW states that you can NOT reduce Hunger to 0 from supernatural blod, only from draining and killing a human.
If this is true human blood would be more powerful in slaking kindreds thirst than kindred blood as it would be the only way to slake the thirst completly.
[V5, page 213]: "Feeding from a vampire of at least two levels of Blood Potency higher than the drinker slakes 2 points of Hunger for each point of Hunger gained by the donor."
This clearly states that kindred blood can be more powerful in slaking Hunger than normal human blood.
[V5, page 181]: "Flaw: (•) Methuselah’s Thirst. Your Hunger can only be fully slaked by the blood of supernatural creatures."
RAW if combined with the statement from p.211 means that a kindred with this flaw can never ever slake their hunger completly as supernatural creatures blood just can not do that.
Obviously there is something missing as these statement contradict each other. The Methuselah’s Thirst flaw indicates that it should be possible to fully slake your hunger on supernatural blood, not only for those with the flaw.
So does the statement under Feeding from Other Vampires:
[V5, page 213]: "A vampire who feeds on another vampire slakes 1 point of their Hunger for each point of increased Hunger they inflict on the donor, willing or unwilling."
I´d say there is an error in the book as these rules contradicts each other.
My suggestion for a fix:
Change the sentence on page 211: "Only draining a human or a supernatural creature of blood, thereby killing them, can reduce Hunger to 0."
Thanks for the comment Marius. Edited my suggested fix to incorporate your advice.