PISL is a Native Language. It developed as a trade dialect to be used alongside speech, as well as for the deaf communities.

Languages are not ciphers. It's not just the same info arranged differently. Languages are capsules of philosophy and culture. Cultures evolve and go extinct, but when you are talking about the results of genocide the extinction of at least these Languages has to be reckoned as a crime against humanity perpetrated by the US and other powers.