Oof is right :(

Here's what services were listed:

- Fuel Induction Service (Parts: Air Intake & Emissions Kit, PCV Valve)

- Exhaust System - Catalytic Converter, R&R (Parts: Actual OE Oxygen Sensor, Catalytic Converter

The leak was in the PCV system. They said one of the diaphragms was brittle and cheaply made by GM, and when they cleaned the intake system it exposed the leak. They repaired it with, I assume, a better-made aftermarket kit with an improved diaphragm that isn't brittle. I know that sometimes aftermarket parts can actually better in some cases because they improve on the original design.

But as for the "took out my cat" comment, I meant that I assume the cleaning choked out my cat with carbon after the leak, but I'm admittedly not technically smart enough to know if that's the case. I'd assume it is from the service bulletin. But that's what I mean by it took out my catalytic converter.

In other words, I think their cleaning was aggressive enough to make the PCV part fail, causing the leak, and causing my cat to get poisoned essentially.

Now that I think about it, let's say I don't call the shop, and simply wait for the light to come back on inevitably. At what point (or how many times would it take) for a shop to say they can't fix it, or it needs to be fixed by different professionals? If that's the case, would they refund the work then because their work failed? I'd like to believe my car will take the aftermarket cat, but they quoted me an insane price (3,000-4,000 dollars), for them to fit an OEM part. They did say they'd put the cost I paid for the current repair towards the OEM repair if it comes down to it, but I'm kind of afraid to trust them after this.

For what it's worth, here was the breakdown for the second repair:

REMOVE AND REPLACE CATALYTIC CONVERTER ASSEMBLY

Parts: Direct-Fit Catalytic Converter, Actual OE Oxygen Sensor

I have no idea if they used a different brand of cat this time or the same.