Of course, you should probably have more canaries.
(If it does, then it seems like the lack of that information is itself information.)
Sounds like there was little to no organization then.
I showed this to my co-worker who managed the technical aspects of a large college theater that also served the town. They hosted multiple large events including bands who had fleets of semi trailers to haul their gear. They had a single contract review person who read everything carefully and then coordinated the teams doling out requirements. As each team satisfied the requirements they would report back.
The problem is that it requires a fair bit of documentation, coordination and processes to make it work, which some festivals do fine and I guess some just don't.
The key is that your head QA person knows who is in charge of what and has a process for holding them accountable, one such way would be to create a checklist of all the items that need to be checked, based on the riders, production requirements, regulations, expected amenities, plussing, etc.
Its also needed for each stage of the process, planning with stuff like speaker modeling, truss engineering, power load calculations, network and communication requirements, etc... on to checking the event area after load in and setup is complete and continuous checks on key items for safety and a reliable performance.
So, its certainly possible to reach an optimized state where you have a negotiated list of requirements and implement them correctly.