(TW: written gore) Difficult BP + Horrifying Nightmares: What next?

[Malum Argenteum]

when he ate at the breeder's, it was about two years ago, and he was kept in a rack and fed a live rat.

Some snakes just do a lot better in tubs, or at least not in glass enclosures (where it is cold, bright, dry, and every predator in the neighborhood is looking in all the time). This shouldn't be surprising. PVC enclosures might be a good alternative for those snakes, in regards to the apparent feelings of security and ease of keeping the environment stable.

Some snakes don't take well to FT prey. Again, this shouldn't be surprising as they look, smell, feel and taste different than something fresh (first hand knowledge not available on that last point ). For them, trying prekilled live feeders might be a good option -- buy a live prey item, and then dispatch it immediately before offering it. I have a couple snakes (not BPs) that prefer prekilled prey at least sometimes (when they get fussy for a stretch of time).

It could be that the vanilla scent mentioned above helps to hide the natural scent of the prey item, often in an attempt to get a snake to recognize a non-natural prey item as food (as when convincing a lizard-eating species to eat rodents). It isn't apparent that this is relevant in this situation.

Once a vet has established that there's no apparent health issues, I'd not get a vet involved unless the situation changes in some relevant way.