The problem with your solution is that what will force NSS to cover? Just because you know about it doesn't make them scared. It's either have to be SEC forces them to do it, which won't be pleasant since they will halt the stock from trading until both parties figure some deals out, or it has to be some mechanism that requires stock recall.
Or it can be like you said, they are hiding something bad, which eventually everyone will jump the ship. I don't think that many people have enough patience anymore.