Most CIS Lambda system use a similar control unit and frequencies. I do not think you will have a problem using a VW lambda with a Audi distributor.
You should be concerned about about the plugged off port. The plate does not care how many cylinders there are. It just measures air flow. The fuel distributor will deliver the right amount of fuel to the engine per air flow. If you plug off a port, you will be removing 20% of the fuel. Most people think that if you plug off one port, the other ports will deliver more. That is a poor assumption and just not true.
Could you make it work, yes, but there are plenty of easier ways to get more fuel. I'm willing to believe a stock fuel distributor will flow enough for the power you want with a few tricks.