Failover to Public Internet if AWS via MPLS fails on Velocloud

One of our customers has AWS using NetBond over MPLS and a DIA connection terminating on a Velocloud. How can I design this or configure this so that if the MPLS ever goes down, AWS is still accessible?

The customer has three sites with MPLS and a DIA. Either we take traffic to other site and use MPLS their to get to AWS or we use the DIA to go to AWS via a Non-Velocloud site tunnel to it. Or if there is any other easy way to accomplish this?

Thanks in advance everyone!