Daas Yochid: I stand corrected, the opinion I quoted is the Michtav Me’Eliahu vol 4 pg 355 footnote 4 who disagrees with the Pachad Yitzchok as you accurately quoted.
“This does not seem appropriate for this case, since the migration to the flesh from the viscera is evident even without scientific theory or microscopes”
I am referring to the earlier stage of development of the anisakis larva where they are ingested by krill when still microscopic. After the develop to a visible size they never leave a host organism, merely transferring from one host to another as the host is ingested. This is not considered shoretz al ha’aretz according to Rav Falk, and while Rav Vaye personally prefers a sevara similar to Rav Kuber’s he lists a number of Gedolim who agreed with Rav Falk.