Universal Work Queue (without taking Adv Collections License)

We have a query on the Advanced Collections form Universal Work Queue.

The customer has already implemented Oracle AP, GL, FA and CM module. Under the current Org strucuture the Operating units are already created and each operating unit is covers different markets. Now we are implementing AR and want to use the collection functionalities available with Oracle Receivables. (Not taken Adv Collections license)

For AR they want to process the invoices market wise and track the receivable balances market wise.  I can use Customer AR territory flexfield for this.  But on the Universal Work Queue how do I restrict the collector not to see the invoices of different markets under the same operating unit.  I cant assign a collector to the customer, because one can have the business with multiple markets.