they probably don't want to be accountable for serious damage claims. They do it for people's attention. To materially disrupt data center construction you need a lot more than a single action

You can get 10% hydrogen peroxide and 32% acetic acid over the counter, so that's probably what they used

Peroxide is a base too. Add it to an acid and you get water.

Sugar water sprayed on the forms and reinforcement before the concrete is poured would work better.