You can try using Grassmann.jl as an evaluator instead, it has a consistent implementation for scalars: GitHub - chakravala/Grassmann.jl: ⟨Leibniz-Grassmann-Clifford⟩ differential geometric algebra / multivector simplicial complex
Those should all behave like regular scalar multiplication, I have also previously given an explanation for the exterior product of scalars Exterior product of grade zero blades