Transaction and Functional Currencies

We are importing transactions for a project which uses employees from 2 different countries: US and Canada. The project belongs to the Canadian OU e.g. the project functional currency is CAD. Since we want the transaction currency to be CAD for Canadian employees and USD for US employees, the transactions are sent to the pa_transaction_interface table as follows:

- for Candian employees, it has CAD in the denom_currency_code

- for US employees it has USD in the denom_currency_code

We have 2 transaction sources:
Labor transactions Non Labor transaction

All the labor transactions are being imported successfully, all the non-labor transactions for US employees are getting an error. Rejections reason: 'Transaction and functional currencies must be the same' or PA_DENOM_ACCT_CURR_DIFF