I tested this with the Ice and Fire mod, and there is a dragon strike mechanic that should deal no damage to tamed mobs like wolves, but it still affect the skeletons. I suspect it has to do with the nbt tags that make them tamed to you

"are you sure they don't just blacklist those specific mobs?" I am sure, I tested with tamed mobs from other mods and they also get ignored.

Forge is no longer being supported, and the mod is getting a total rewrite for Fabric. Here's why.