I had exactly the same problem. I tried epoxy a couple of times but eventually bought a new air filter housing. You have to buy the whole thing if you get it from a dealer including a new filter plus top and bottom.

It cost me $133.65 from Caliber Motors which is a Mercedes dealership that discounts parts.

I also eventually twisted the metal off the rubber on one of the mounts and replaced that as well.

I am now very careful about not overtightening the nuts.