There's some risk to this, but one option is to use a different path/account that will still demonstrate the functionality to the audience. Of course, there's the chance of having it fail on you again, but if you have a feeling what's causing the issue and know how to work around it, then it might help the perception of your app from "not working at all" to "not fully tested".

If you have a team behind the scenes that can fix it within the presentation time, that might be a good demonstration of your ability to recover from the inevitable issues that will arise.