I get the impression that Zuikaku was the first ship in Asgard to manifest a shipgirl. If that's the case, there was probably a post-Ragnarok research program to see what had happened that ended up with a few conclusions:

1. (A list of events and conditions) is what made it possible for Zuikaku to manifest a shipgirl.
   
2. It is possible to recreate these events.
   
3. It is morally wrong not to do so for all Einherjar ships that have the potential to have a shipgirl.
   

If I'm right, Skuld probably has the information necessary to explain what's happening to Fubuki, perhaps in Appendix C or so of the report on shipgirls. ("It is hypothetically possible for a shipgirl to be affected by a Midgardian operation to salvage their original hull. Given the advances in shipbuilding technology, the probability that any such operation would be launched is effectively zero; between the outdated materials and requirement to repair the damage, it would be more effective to build a new hull.")

Peter Eng
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Insert humorous comment here.