Can you help me understand the dissatisfaction of my client [name withheld] with her higher self channeling? What was she expecting to learn about her soul’s origin and about her cat that did not come through?

Indeed, as you suspected, she was expecting to learn she is quite special in her origin and her uniqueness among humans. This is false information she has been given that is greatly cherished, and so her higher self was simply avoiding confronting that issue head on and so take away her belief. As you know, this cannot be done and will never happen wittingly by a divine being unless there is an error of some kind on their part as this is a transgression into the free will zone. So this is one of the unfortunate things that will happen from time to time when people come to you with preconceived ideas and wanting your simple corroboration and then it is not forthcoming. They will consequently blame you and find fault with you in not seeing deeply enough or divining the true secret answer to their quest they wished to have. So this is not a fault of yours, it is a dilemma of the higher self. She believes she has had a prior life with this cat as a human being. And so it is not the incarnation of a former loved one among humans, it is indeed an animal and it is a special animal to be sure, as it has had previous lives with her, but that was not what she was after. And again it put the higher self in a bind in not being able to be forthright and thereby take away a cherished belief of hers.