Here is a list of all tables/columns in 8.0.12 where there is a customerid.
Code:
Address.CustomerID
AuditLog.CustomerID
AuditLog.UpdatedCustomerID
CouponUsage.CustomerID
CustomCart.CustomerID
Customer.CustomerID
CustomerGiftRegistrySearches.CustomerID
CustomerSession.CustomerID
FailedTransaction.CustomerID
GiftCard.PurchasedByCustomerID
GiftCardUsage.UsedByCustomerID
KitCart.CustomerID
LOG_CustomerEvent.CustomerID
Orders.CustomerID
Orders_CustomCart.CustomerID
Orders_KitCart.CustomerID
Orders_ShoppingCart.CustomerID
Orders_ShoppingCart.GiftRegistryForCustomerID
PasswordLog.CustomerID
PollVotingRecord.CustomerID
Rating.CustomerID
RatingCommentHelpfulness.RatingCustomerID
RatingCommentHelpfulness.VotingCustomerID
SearchLog.CustomerID
ShippingImportExport.CustomerID
ShoppingCart.CustomerID
ShoppingCart.GiftRegistryForCustomerID
So you might have to take care of them aswell as the [Orders], especially [Address]