I’m sorry you’ve had such a bad experience. If you have feedback we’d happily take it to improve developer experience.
If you’re on Ubuntu 18.04 (like the link you posted says), I believe you should be able to use apt-get to install all of our dependencies. Have you followed the instructions on our README 1? It says it’s been tested on 16.04 at least. Or are you building everything manually?
The instructions for installing and using ONNXIFI are on that page, but I haven’t tried it myself. That page does say it can be a little tricky but I do not know the details there. If you try and run into issues you can always reach out for help.