Intercompany Invoice and Payment in BC

Hi Experts,
I want to map intercompany process for my client.
Below is my scenario
1. Master Company
2. Trust Company

Invoices related effect should happen in Trust company (Expense account, Payable Account)
Payment to be done from Master Company Bank Account.

Where should I create my Vendor Invoices so that account should affect in Trust Company?
If I do the invoice in Trust company then G/L Account effect is as per expected but when paying the amount from Master Company, there will be no entries to apply in Master Company since, Invoice exist in Trust company.


Can I create invoices in Master Company and have the G/L Effect in Trust company? Yes, we can do that but Payable account in Master Company will also get effected. Is this valid?

The above scenario also includes one business rule where entries from customer also to be considered while payment to Vendor in case related customer with outstanding balance in Master company.
I am using Payment Journal and Purchase journal for payment and invoice respectively.

Need experts advise on my above request.