workspace:FindPartsOnRegion3WithIgnoreList isn't finding anything?

I have 2 separated points from which i want to construct a Region3, and there are several parts located within that region so I can confirm that it's working.

it isn't.

Here's my code--

local reg = Region3.new(script.Parent.Parent.C1.Position, script.Parent.Parent.C2.Position)

while wait() do
    local pts = workspace:FindPartsInRegion3WithIgnoreList(reg, {script.Parent.Parent.C1, script.Parent.Parent.C2}, math.huge)
    print(#pts) -- Prints 0???
    for i, v in pairs(pts) do -- Nothing??
        print(v)

    end
end

Edit: Here's a picture of the situation, the two points are neon red -- https://gyazo.com/f92ba09cecc4a8bab49c661851f33dc1