If an automated roulette machine (or any other wheel) actually varies the speed of the wheel while it is spinning, will custom variants still win?
YES. Irrespective of the speed of the wheel or varying spin speeds, the physical properties of the wheel do not change and therefore generate inevitable long-term patterns that can be used to overcome the house edge. If you think variation of wheel speeds makes a difference, you need to think along the lines of many spins rather than just a single spin. Over the long term, the casino could even use a different ball on every spin, and still long term predictable patterns would form – it is absolutely unavoidable and inevitable.