Remediation company contract

[Mark Forest]

I have explained in prior posts that a broken water pipe did severe damage to my house. The insurance companie's remediation co did a lot of demo work and set various machines to dry the house. Now they say they are done and want me to sign a contract saying the job was done to my satisfaction and I will not hold them liable for anything occurring in the future. 

Well I am not an expert home inspector or otherwise qualified to say the job was done right. What if they missed something? Shouldn't they be giving me a guarantee? What is standard practice?  Thank you to all who give accurate answers.