If you charge auto gratuity or a service charge, that amount will be included in your sales income. Commerce Sync does not have the ability to separate these amounts in the transfer nor do we have a setting to separate them on the Commerce Sync Dashboard. If you want these to report to a separate account in your accounting solution, you will need to do a journal entry to remove that amount.
We are unable to separate them or map them to a liability account as the IRS describes them as "Charges added to a customer's check, such as for large parties, by your employer and distributed to you should not be added to your daily tip record. These additional charges your employer adds to a customer's bill do not constitute tips as they are service charges. These service charges are non-tip wages and are subject to social security tax, Medicare tax, and federal income tax withholding."