You are only liable if you accept the liability or a court determines you are liable. This is why you have liability insurance.
Also, you need quality legal help and not rely on advice from random people on the internet who have no legal expertise.
Once you start documenting stuff, you have a paper trail. IMO, and you need to review this with an actual attorney, you are potentially accepting liability by commenting in writing about things you did not work on. And given some of the crazier things people have suggested should be done on this very forum, you may be proving in writing you are incompetent. You really want to get on the stand and defend the idea that somehow pounding a ground rod at a pool will make it safer? You will get shredded. And this might be over something you did not even get paid for.