Completing "You Only Die Once a Night" without Celerity?

So, I ended up stumbling across a borderline exploit that worked remarkably well for this:

As soon as you finish talking to Romero, run downhill, away from the gates, to the Mausoleum (where the tunnel to the Nosferatu warrens is), and run behind the Mausoleum. Chill out there, kill any Zombies that happen to find you, and wait until the clock is down to around 1:20 or so.

At about 1:20, run up to the lower gate and kill the zombies attacking it. Hold them off and keep them under control until the clock runs out. The upper gateway will remain safe through all of this and if you can keep the lower gate under control for about a minute, you'll win.

It is possible to do so but it's very difficult. Try to target zombies that spawn near the gates, "auspex" should help indicate which ones are a priority. I found melee weapons worked better for me than guns. Don't let any of them get close to you however, if they grab you it takes too long to shrug them off.

Do you particularly want to do this quest? The alternative "Pimpin for Romero" is a lot easier.