That does look like they damaged it. If you had it documented and returned once for a leak, dud you try and take it back and tell them it is still leaking in the same spot.
If you do it yourself, just get the oem.
You may just be able to press the pedal further. You wouldn't have any brake broblems with a small vacuum leak while operating. It's only after the vehicle is off for an extended time and the vacuum is gone.
You watched too many Safelight commercials. Drive it!
If you have seen any shoot em up movies, where the windshield is full of bullet holes, and it takes thr guy 4 or 5 kicks to get the windshield to fall out? That's more realistic.
Kind of risky, but if you flick off the loose paint you will see either white powder or the dirt that they painted over. If you see dirt, it was there when you bought it. It could be seem sealer that got out of control and never cleaned off.
So they are telling you, that if you can't see it from the outside, it's okay? I never even looked under the hood for corrosion. I only have seen it on the exterior surface.
I'm not positive, but most brake pedal switches are depressed with the brake off. When you depress on the pedal the switch is relaxed, and now completing the brake/starter circuit.
Brake pedal switch. The problem is when the booster is flat ( no vacuum), the pedal is very hard to depress, enough that you can not activate the switch. No start, no brake lights.
To rule out this being the issue, if you see your brake lights come on, this is not your starting issue. Same switch is used. So if you cannot depress the pedal enough to activate the brake lights, this will be your problem.
If you do end up having it towed to a dealer, be ready for them to squawk at switch that you have installed. They may not want to play with your batteries if you modified it.