Never seen Tinbergen's questions applied to ethics before. Seems like a bit of a mismatch.

First off, we are presupposing that animal welfare is morally good and that what humans value should align with what nonhuman animals value. You could make a case that this is what ought to be right, but that's not the thesis of this paper.

Second, and closer to the paper's argument, it's weird to think an animal's values will align with Tinbergens questions (answers). For example, every animal wants to consume food, but not every animal values becoming fat. Fish don't value having gills. Answering these questions in a satisfying way would also introduce circular logic, or absurd answers, like fish value gills but arent aware of their values, and humans value fat but deny it if you ask them.

Big fan of the four questions, and of animal welfare, but this paper doesn't use the former to help the latter.