Yeah you can do the run with the DLC installed!

I don't know if Steam took away downpatching as I've heard mixed reports over the years, but this guide was last updated 2 years ago https://steamcommunity.com/sharedfiles/filedetails/?id=1086279994 it might help

if it doesn't work out you can probably ask around the discord for an older version of the game, but you will probably be asked for proof of purchase to avoid piracy

After the October patch last year it's become incredibly rare and potentially even just a lag clip. In other words, nah it's not really possible any more unless you down-patch.

You can print from anywhere in the javelin if you open your journal