I fear that finding a way of attacking fundamentalist Islam while not being villified as one form of evil (sellout) or another (apostate) may not be possible.

And if it is not possible, then all your efforts at accomplish it will prove wasted efforts. Efforts that could have been spent working on something that is possible.

There are PLENTY of people who work against fundamentalist islam, some from within moderate islam, some from a position that abandoning islam is the only reasonable choice. I think you would do better finding good information about your choices for resisting by studying these people and what they do and how they do it and what they say. As a non-believer, I still find I have great respect for BOTH believers and non-believers who work against fundamentalist stupidity, violent oppression of non-believers, non-education of women, crappy education of men. I have worked with many believers who I respect greatly as good people and good scientists, enough to know that the moderate believer is not an an enemy of rationality the way a fundamentalist is. And I reach this conclusion as a non-believer.