Can I take payments if Repair Order information is not automatically poppulating?

Yes.

If the connection between the DMS and Kaarma is temporarily down, Kaarma will not be able to pull the amount that is due on the invoice and the contact information for the customer

However, Kaarma's payment system will still allow users to use the swipers. After entering the RO# into the RO/Reference Number field in the Pay Now screen, Users must manually enter the Amount and applicable Contact information before selecting the Pay button.