“law that explicitly says migrants can apply for asylum even if not at a port of entry.”
Even if they got in illegally? Can you give me a link to that law?
U.S. Code Title 8 Chapter 12 Subchapter II Part I § 1158
"Any alien who is physically present in the United States or who arrives in the United States (whether or not at a designated port of arrival and including an alien who is brought to the United States after having been interdicted in international or United States waters), irrespective of such aliens status, may apply for asylum in accordance with this section or, where applicable, section 1225(b) of this title."