Let's be honest, there's no qualifications required beyond a popularity contest and the right connections.
A liaison officer should have a working grasp of risk assessments and mitigations, high temperatures is a basic and a briefing to fans around alcohol in take and water should be high in the list of priorities.
I'm not sure why people are surprised about bulky items being seized prior to the game, given the authorities approach to missiles, disorder, etc but go to an NFL game and you get a briefing on what you can bring in down to the need for clear plastic bags that can be visually assessed with no opening up required.
If someone has a copy of the job description, that's the easy to assess the performance of the position and not what we think should be done.
I will say that communications were limited at best.