There is an option --header <device or file storing the LUKS header> to use a detached (separated) metadata device or file where the LUKS header is stored. This options allows to store ciphertext and LUKS header on different devices. It means that we can have volume full of random crap without any determinate signature. Description of this option contains a bit more information, precautions and warnings, but the essential is just that. Yet I earnestly recommend you to read that fine
Assuming you have full access to the system and don’t have an ‘official’ way to remove it. Follow this to remove any full disk encryption software, even if you do not have keys to the full disk encryption software. You do need full admin rights and physical access.
It’s important to understand that security is an emergent property of your overall product or system health — it’s not an isolated feature that gets shipped and is then relegated to minor upkeep. Rather, similar to your own personal health, security requires ongoing maintenance and consistently applied proactive care.