Disappear back into the woodwork. The key here is ramping up any anxiety a customer is already feeling from the situation. This is what trolls pray to their God for, a chance to relentlessly antagonize others without the fear of retribution. If Havelock goes down for good, their delight will eventually end as this thread closes and all of their targets move on.
If the site comes back up, they can escape being caught in the sunlight and wait for another opportunity to present itself. Something to consider is the trolls have been correct on numerous occasions and wrong on several. If you see a troll stepping up and admitting he/she was wrong about Company X's long term viability to date, then that individual is simply not a troll. Providing attention to a troll is akin to draining your mental equity into their personal fund. It often reflects poorly on the shareholder when they fall prey to this 'one trick pony'.
Yeah, that catches it nicely.
Well, I try my best to limit my exposure to this kind of worse than useless crap. Only see it for a few minutes, then it´s gone forever.