Garnishment. A legal procedure by which a creditor can collect what a debtor owes by reaching the debtor's property when it is in the hands of someone other than the debtor. Garnishment is a drastic measure for collecting a debt. A court order of garnishment allows a creditor to take the property of a debtor when the debtor does not possess the property. A garnishment action is taken against the debtor as defendant and the property holder as garnishee.
Salesforce: Build Parent/Child Relationships. Salesforce.com For Dummies, 5th Edition. In Salesforce, you can link multiple offices of a company together by using the Parent Account field on an account record. And you can create multiple tiers to the hierarchy if your customer is organized that way.
You did not mention how you ended up with these separate accounts. So, it's hard to speculate. One is automatically created by QBO as a default account for sales tax which you do not want to delete, most likely named Sales Tax Agency Payable. Other account is probably newly added (or created during conversion).