Would a crank sensor kill all boost though? Not having seen the car or kit in question and I'm far from an expert at the VQ35DE engine, but the symptoms sound more like one of the pipes post-turbo but before the TB have popped off: At least, that's what I've had before on previous aftermarket turbo'd cars. If this had happened, then would the car going lean off-boost/rich on-boost cause the crank sensor failure?
Sorry, not trying to sound like a know-it-all-Nancy here or anything, I'm genuinely interested as to what caused the failure as going FI is something I'm looking at for the future of my own car, and I'm more experienced with turbos than superchargers so that's probably the route I'd take. Just eager to learn, that's all!