Damage to hood due to leaky pipe

I need advice. I park my 535 in my owned place in my condo garage. The garage ceiling is covered with drain pipes, one of which is right over the front of my car (you can see where this is going.)

I got home from a trip last week to find that the pipe had been dripping some substance onto the hood while I was gone.

There was chatter on the the building email list about plumbing problems, backed up drains in people's kichens, etc. and that "some water' had found it's way into the garage." Given the look of the mark on my car, my best guess is that what dripped on the car included drano.

Some of it splattered onto the windshield, and I was able to get it off with some window cleaner, but the stuff on the hood won't budge using normal mild cleaning substances. It "looks" like it's etched in, but when I rub my fingers over it you can tell it's raised making me think that the substance might actually be caked onto the hood rather than etched into it. Before I jump to conclusions I'm willing to try a couple more things in hope it will come off, and am looking for advice.

I'm attaching a picture of the spot, and fear I'm looking at a total hood repaint (on my 4 month old car.) From previous experience, I know the board will worm their way out of any responsibility, so this will likely wind up being my problem.