which is hilariously unlikely given how dogs respond to fent
What exactly do you mean by this? Dogs respond to fentanyl exactly the same way that humans do....it just takes a larger dose because dogs are less sensitive to it that humans. If a dog is exhibiting signs of fentanyl overdose, all that means is that they've ingested a larger dose than would be needed to make a human overdose, and especially if the dog's owner is already saying it's happened before with the same dog and they recognize the symptoms in progress.
Considering it only takes a few grains of fentanyl to cause overdose in humans, it's not far fetched to think a puppy could ingest or inhale that much accidentally, especially if being transported in the same vehicle where there is known fentanyl possession taking place. Keep in mind, the body weight of a puppy is a fraction that of a full grown dog.
Puppies can and will eat anything regardless of whether it's an actual food item or not.