Attempting to use drivers/shape keys instead of weights/bones with blender/UE4.21.2

I’m trying to import a mesh I’ve made and get it working in Unreal. I have it functional in blender. This is just a test mesh, I included the .blend file if anyone wants to take a look at it.

The idea here is I’m using shape keys to morph the car body, and I’m driving those shape keys with bones. When I import the mesh into Unreal, and try to simulate, moving the bones around doesn’t drive the shape keys. I’m wondering if there’s an import setting I need to make sure is ticked?

Caveat. The bones are weighted to portions of the mesh (with no weight, other than the root bone at full weight) not because I wan’t them to do anything, but because this is how the game gives you something to pull on. It’ll highlight the portion of the body where the vertex group is weighted to the associated bone, and that highlighted area is where you interact with the body, causing it to morph. The way it works in game now is with just standard weight painting, weighting to the bone and whatnot, and that all works just fine. I’m just trying to come up with a better morph method to do more dynamic morphs.

Import dialogue asks if you want to import morph targets. In the anim graph, look for a driver node, use that to rebuild your bone-morph drivers