Permanent juggs verification?

Last night my friend and I decided to play with some randoms. This one random we get matched up with begins to tell us how he discovered perma-quick revive and perma-juggs. (His story was straight-on and sounded legit with how he discovered perma-quick revive) Definitely thought he was bullshitting on the perma-juggs though. So I asked him how he got it and he told me that you must not get hit by ANYTHING (no denziens, no fire, no zombies, no fall damage, absolutely no damage markers can be shown on your screen) by Round 13 and you will get permanent juggernaut.

My friend and I tried it for a couple games and found it almost impossible to do unless you have three other players basically doing all the work and you just stay on the bus trying not to get hit any zombies.

I plan on trying this out with a full party soon. Although I'm hoping someone will be able to de-bunk this or verify it before I go and try it.