The controller by itself is not the crazy part, as controllers are also used by the military in some countries. The mental part is that they relied on a wireless connection, which any gamer will know can be highly unstable/unreliable. Military application of controllers always uses a wired connection.
They did have spare controllers on board in case it failed, but this particular model (Logitech G-F710) relies on a 2.4GHz cordless connection, meaning you need a USB dongle plugged in for it to connect. Each controller will only connect to the specific dongle that it was shipped with, and judging by the way this shitfest went, there is a real possibility they were not aware of this. So all of those spare controllers would've been useless unless they came with their corresponding dongles on board.
Then there's the fact that they used a 2011 knock-off brand, which again, every gamer will know is highly unreliable.