1997 Acura Integra Question about legitimacy of repair

Hey everyone! Hopefully someone has had an experience similar to mine and has some advice because I'm between a rock and a hard place here and I don't want to sound like a jerk if this situation is a common occurrence.

I recently had new rotors and brakes installed on my car and our family mechanic who I've known for almost a year basically ruined 2/4 of my struts; or rather, his lift did. The first time I met him he told me a story about how the tire and suspension assembly hanging free from the lift ruined some woman's car that she brought in and how he couldn't do anything about it because "if the struts were fine there wouldn't have been an issue; I don't know how tire and brake shops avoid it". Anyhow, I'm now in the same situation as that anonymous woman and I face having to harass someone who is intertwined with the rest of my family just to get told that it's not his fault.

To clarify, I could take almost any kind of bump (including speed bumps) going as fast as I wanted, and the car wouldn't so much as flinch. I have difficulty believing they were in such bad shape that a bit of hanging would lock them up, and if that was the case--then why didn't it happen to all four of the struts (it's only in the front)? He never has an issue explaining what happened in detail and even showing me the parts after wards, but it's 800 to replace all 4 and I'm afraid if I do just 2 then I risk ruining the front pair all over again if the rear pair ever goes and the suspension has to dangle again.

That being said, is what he's claiming even legal? If there wasn't an issue before I took it in the shop and it came out with one, regardless of how it happened, is he not responsible? It's like if he tapped a windshield by accident and it shattered because it was old and fragile--regardless of it's condition, it was still working prior to bringing it in?