I forgot where the place is but it pretty small but its complete with an octagon cage.
The UFC has their own facilities to conduct fights without any audience and their performance center is capable enough to conduct fights with just the officials, Dana White will not reveal those details to avoid back lash from media until the last moment.
They are placing the fighters health in danger if they continue with this, its hard to detect which person is already infected with COVID-19 because there are those with no travel history, no signs of being infected but after a few day after testing they are positive.
There is no doubt that the UFC is taking a huge risk by carrying on with the event and if there is a mishap and if someone tests positive after the event then the company will be under fire and will face sanctions and fine and with the stakes so high i am sure Dana White will take every steps to monitor and test all the individuals present in the arena to make sure anyone who is part of the event is Covid free.