A reader of this site reached out to me with a recent photo of the restaurant which has a spray painted sign that says "Closed for Remodel" (pictured right).
Also, the restaurant Facebook page has not been updated since March 2015, and if you call the telephone number of the restaurant, it is disconnected. So while it is supposedly closed for a remodel, all other signs point to a long-term closure.
You may remember the restaurant was listed for sale when the episode aired (from the original update), and the restaurant is apparently still for sale.
The Restaurant Impossible makeover happened in January of 2015 and the episode aired in March of 2015, so it didn't take too long for this one to close. The status of Whabah Steakhouse has been updated to 'Closed' on the Restaurant Impossible Update Page and this is the first restaurant from season 11 to close. If they actually are remodeling just months after Restaurant Impossible and the restaurant re-opens, I will re-update the status.