Haven't heard back from Van's but tech counselor confirmed the best course of action was just to sand out all the surface corrosion and prime it. Got most of it out with 400 grit sand paper and the some 3m pad. Set it aside for now. I will scuff it good again before priming.
3/29 update: spoke to a Van's rep. He was confused by it as well. He said they would just send me new parts. I told him it was really just the forward spar that was bad so they are sending a new HS-1002.