It is very unlikely if not impossible that you can re anodize unless you are willing and able to remove the affected areas and give them to an anodizer. Also not likely to match the finish in any way satisfactorily.
My suggestion, as someone who works with aluminum a great deal in my business, is to clean it and leave it exposed to air under cover of a roof , preferably outside , and let it anodize itself. It won't take that long , just ask people who polish and wax their trailers. They have to do that to keep the aluminum from oxidizing, which anodizing actually is.