Forget about them offering legal collection; too often these days, you'll almost have to bring legal action *against* QuickBooks to get them to give you the money your customers *did* pay through QuickBooks' merchant system.
I appreciate you for reaching out to the Community, Wvd1. Let me provide some information regarding this.
As of the moment, offering legal collection of invoices is currently unavailable in QuickBooks Online (QBO). Since this involves some personal matter that only you and your lawyer should discuss, it's best to seek your lawyer's advice and consider your options thoroughly before taking any action.