I think you're thinking way too much on this simple matter. Simply drill through the center of the stripped allen and slowly drain away the aluminum shavings from the drilling. Then remove the entire drain plug. There is no real reason for any sort of sealant on that plug. They just don't leak there,--unless WAY over torqued and then it is distorted. If you'll drilling that out, I wouldn't be worried about aluminum chips working their way into the engine. As the oil is draining, it will sweep it away with the oil as it drains. Just do this after a little driving,--to warm it up a bit (not too much is needed with these light oils).
Dan