^ it's been a while, but isn't the vocal cord parasites thing perfected in the Africa level, and you also rescue Code Talker from there, too?
You get Code Talker... But he's irrelevant and doesn't do anything aside from give observations. Even the Skull Face plan he gives is not only wrong, but contradicted in the very next level.
The perfected parasites were finished before Venom even arrives, so they could have been revealed in Afghanistan just the same way.
yeah tbh, it's been so long that, I forget Code Talker's purpose ---