VA and DME

We see quite a few VA patients from the clinic adjacent to ours. Its been discovered if we bill diabetic shoes directly to the VA, they are paid. However if we complete the RFS form (required for MRI orders, referrals, NCVs, etc) the patient is sent to a VA contracted DME provider. At this point we are not a VA DME vendor. Am I able to bill the VA for diabetic shoes/inserts and/or orthotics directly? Am I at risk of a recoup demand in the future if I proceed with providing these to VA patients?