USA EE travelling and working occassionally in Canada

Hello,

We have USA employees that work for a few days in Canada but whose payroll is run and paid in the United States.

For the days they work in Canada, these employees are supposed to pay taxes in Canada and we do pay taxes on their behalf by submitting from accounting tax payments to Canada Revenue.

At the end of the year, we have to add these tax amounts paid on behalf of the employee to their YTD income and calculate the corresponding Tax Deductions and we are wondering what is the best way to do this. We would like to find a pay type where we can add these amounts so that taxes are calculated and a pay stub is produced but that no dollars are paid to the employee.