Rather than let this be a roadblock for you until a Sasquatch model falls out of the sky into your downloads folder, design the unit with a placeholder model. You can pick something from the normal wc3 model list but change its vertex coloring and size to make it appear noticeably different for now. Obviously you do not want just a big yellow wendigo (or tiny purple wendigo, or whatever else) long-term, but you can continue to work on your Sasquatch race even without such models.
Gameplay, abilities, and balance can all be worked on and finalized without access to the perfect model. The vast majority of all actual game development occurs with placeholder models/animations/textures/UI/etc. so this is quite representative.