I'll take the lawyer's word over you anecdotes on this one along w/the surge in rescission and this administration history w/immigrants. No one is denying background checks were done on immigrant recruits by the way.
https://www.nytimes.com/2018/07/06/opinion/trumps-immigrants-military.html
Some of these immigrants will now carry discharge documents that unjustly and incorrectly label them a security risk. Moreover, their path to citizenship will be delayed, perhaps permanently.
Many immigrants were rejected for service in the U.S. military decades ago due to being security risks -- why don't you have the press go interview them. They are easy to find.