[SalesForce] Error while deploying a Change Set: Could not find related list [AttachedContentNotes] for entity [Contact]

In case anyone needs this, your Milestone Criteria in the Entitlement Process cannot have the advanced filter logic for the change set. If there is advanced filter logic, the change set will fail. Just create the Milestone Criteria with all ANDs (no filter logic) and then when you get to production, change to the filtering (AND / OR) that you need.

The issue you're having is related to the nature of person accounts. A person account takes most of the information from contacts that aren't on the account object and adds it to the account detail page; duplicating it in the database. If you have account record types other than person accounts, you'll want to check the contact's record type before you attempt to display your related list.

If the only type of Accounts you use for Cases are person accounts, then what you'll want to do is change your list to the account object for that contact since each contact will only have one account. If that's your situation, it actually would be preferable to use the accountId rather than the contactId to track your cases. I recognize that's not the normal way cases and the console are configured to operate. Perhaps if you do some additional research on person accounts, you may find a solution for this particular issue that's out of the box since it's clearly the cause of your problem.