I love repurposed projects!

You didn't think about just using a cheap $25 Chinese controller? They will ignore missing hall effect sensors, although are a little noisier on acceleration with no halls.

Also you don't need power to test hub motors, you just short any 2 of the leads together and spin the wheel, if it hard to turn, thats good. Do the same with either one of the leads you already did and the one you didn't, again, it should be hard to spin.