While I admit it may seem radical to render the entire sugya of Gemara and Rishonim irrelevant, the bottom line is if the anisakis is never shoretz al ha’aretz even when it originates outside the fish how could it possibly be assur.
Additionally I didn’t make this up, Rav Vaye quotes this sevara from Rav Falk and writes that Rav Fisher, Rav S.Z. Auerbach, Rav Greiniman and other Gedolei HePoskim agreed wit it (I don’t have the sefer in front of me so I am listing the names from memory). Rav Vaye personally is concerned that the larva may be of a size significant in Halacha before being ingested by krill, as scientist’s definition of “microscopic” he considers too large. Additionally he quotes Rav Elyashiv as considering a sheretz “shoretz al ha’aretz” even if it was shoretz only at a truly microscopic size.