Please do so. I made two folders for gw and I'm still able to launch only one copy of the game.
I was wrong when I said that simply creating a second location would work - I edited in later that I was using GW Launcher. I added both accounts to the launcher and pointed one account at the first location and the other account at the other location. This is how I am able to launch both at once. I do not need to use the .dat patch as I'm not trying to use a single install. I do apologize for the initial wrong advice, that was my mistake and I'm sorry.
GW Launcher isn't sketchy, and if you are worried it is open source so you can technically compile it yourself to run it.