You could probably edit the code for a short time in your page, but the visual is served from a CDN, so each time you add or amend it then it's going to reload the same code from that resource and nix out your modifications.
I see from the thread that this is a specific issue with the visual, and looks like it's logged in their repo here, but doesn't have a lot of traction.
I think that if you're considering taking matters into your own hands (or you have someone that can help), then it's a better approach to clone their repository, asses/fix the source code and then submit a pull request for them to approve. You'll have a much easier time finding the problem if you can debug locally using some of the SDK tools rather than taking a stab at editing minified code. It will also have the benefit of providing the solution for other users.
Probably not the answer you're looking for in the short-term, but will save you a lot of hair-pulling.
