The installer always has that gibberish unfortunatley. I had a similar issue so would recommend using this tutorial:

If you are on windows 10 then I would recommend creating a folder in your program files and copying the contents over from the open iso file to the directory including the patch from the resource section. The channel I have linked above also has a tutorial covering this technique.

Are you using "game capture" or "window capture" on OBS? You need to use window capture and RE2 should appear as one of the selections as long as you have it open. I wouldn't recommend playing the game full screen, you will have all sorts of issues with it.