Okay, so I was looking at the files and I came up with an explanation for this. I embellished it a bit, so do with it what you will, but this is just what I think the meaning of Claude Huggins is. I have two theories.
First (and simplest), there is the theory that Claude Huggins is simply filler text. A Lorum Ipsum, if you will. It's the placeholder name that they use as default where a canon name will go later. That was in a beta file. Perhaps the canon name just never made it onto that particular file.
Second (and more fun), I did my usual "tragic headcanon backstory" thing. Claude Huggins was a pseudonym that he came up with to hide his identity from the Americans hunting down refugees and fleeing war criminals. There was a man who helped him get his identity in order, once he arrived in America. After all he'd been through, of course he'd be a bit paranoid about being found out, especially with the McCarthyism stuff going around, and the Red Scare making people so suspicious of everyone and then the Doctors Trials for war crimes, etc.. So he had to get a new name, a new ID, a new life, a new story. He had a name picked out and everything was ready. The night before he was going to go finalize the fake ID stuff, his friend took him out to a bar for a celebratory drink. Suddenly a fight broke out. A gun was pulled, shots were fired, and despite Medic's best efforts, his friend died from his wounds before the police and ambulance arrived. So he took his friend's name, Claude Huggins, to keep his memory alive. He even had a plaque made, since he couldn't afford a gravestone.
TL;DR: Medic is sentimental.
Anyhow, what about the Claude Huggins in the L4D universe? It couldn't be the same person, of course. The time periods in which the games take place are too distant. Perhaps it's just a coincidence. Perhaps it goes back to Reason One-- Claude Huggins is a default name, nothing more. Perhaps there is an eerie connection, and perhaps nothing I say will pull you from your conspiracy trails. Believe what you will. I'm just putting this out there. Thanks for reading!