You could do this instead of setting a path..
Open RUN tab in the IDE
Click OUTPUT EXE TO SOURCE FOLDER
Now that just makes it so the exe is placed in the same folder as your QB64 .bas file. So if you want the exe folder in say, C:\myfiles, you would need to put or create (save) the BASIC file to that folder, first. Now I actually haven't ever tried this so please someone else correct me if I'm presuming incorrectly or explain to the OP if there is a anther way. It's been so long since I've compiled from the command line I can't remember if that's an option.
Pete