Hello, rpreston.
I'd like to show you a service that'll help your employees track their own time and mileage.
We actually have a service called QuickBooks Time where you can set up your employees to let them track their own time and mileage. You can sign up for a subscription here: https://quickbooks.intuit.com/uk/time-tracking/pricing/.
This service also lets you integrate with your existing QuickBooks Online account. This way, you can easily import your customers for tracking and export timesheet data for payroll in the Online platform.
An overview about the settings and features can be found here:
If you need to view your payroll data in QuickBooks, you can check out one of these articles depending on your subscription:
I'm always hanging around in the Community space, so don't forget to visit this thread if you have concerns about QuickBooks Time.
Do you have questions about your payroll tasks in QuickBooks Online? Let me know the details and I'll help you out.