Why do human vaccines affect different animals differently?
One big reason for the difference is how close the vaccine's epitopes match the natural epitopes in the animals. When they are similar an attempted immune response to the vaccine will either tend to give an autoimmune response; or no response as the relevant immune cells were destroyed during maturation (to prevent autoimmune diseases).

The reports of autoimmune disease from SARS-Cov-2 (kawasaki disease) would seem to reduce the targets for a successful vaccine.

Sorry no refs on this.