I brought up this with an elderly JW carter today.
He has no problem with the notion that animals were vegetarian before the flood.
He concurred that coprolites have been correctly identified as fossilised turds.
He agrees that those coprolites which appear to contain bone fragments do indeed contain bone fragments and that this is clear evidence of carnivory.
He also agrees that those identified as being from dinosaurs were indeed from dinosaurs.
He recognizes that dinosaurs pooping bone fragments must, therefore, be post-flood and that Noah must have had dinosaurs on the ark.
He was familiar with the consensus that an asteriod impact pretty much saw off the last of the dinosaurs and this event coincided with a mass extinction event of other species too and saw no reason to object to this.
He didn't find anything puzzling in the idea that Jehovah should seek to preserve animals on board the Ark and would then sit back and let an asteroid cause most of them to go extinct.
He didn't worry at all that no Bible writer, nor any other ancient text mentions the disruption caused by this massive post-flood extinction event.
We were stood a little way from the cart but his wife was visibly shocked when she heard me say that "I find it odd that you believe there was a post-flood mass extinction event which killed off a huge proportion of plant and animal species, including the dinosaurs Noah had on the Ark and yet you're quite content that the society literature never explores this key event in human history or the Bible's silence on the matter."
Well, at least this JW is still prepared to speak to me. The most regular JW in town, Sister Battleaxe accused me of being a demon-possessed apostate and won't talk to me any more.