You need to be in contact with the Fee Basis Unit of your VA area.
Here is the verbiage that I found when I had to research this:
1) Treatment was rendered for an adjudicated service-connected disability or a condition associated with and held to be aggravating a service-connected disability, or for any condition in the case of a veteran who is found to be in need of vocational rehabilitation and for whom an objective has been selected or who is pursuing a course of vocational rehabilitation;
2) Treatment was rendered as a medical emergency of such nature that delay would have been hazardous to life or health;
3) VA or other Federal facilities were not feasibly available.
My ER visits were directly connected to my SC. But I think as long as any connection can be made to your SC and the ER visit, you should be good.
I am not sure if it falls under the same office, but when I went through this, I found out that I had to send my bills to the Consolidated Fee Unit in Flowood MS.
Here is the link for the Houston VA system site on it:
https://www.houston.va.gov/emergency_care.asp
Here is the note at the bottom of the page:
Veterans who are enrolled at the Michael E. DeBakey VA Medical Center or one of its outpatient clinics in Beaumont, Conroe, Galveston, or Lufkin should mail their claim to: VISN 16 CFU, P. O. Box 320164, Flowood, MS. 39232. For questions after you have submitted your claim, call (601) 933-7700.
I have had to tell the outpatient free standing ERs to send it to the correct address. They kept trying to send it to the regular Tricare address in Colorado. Most of the billing departments do not know of the VA ER Fee basis mailing address.
See also:https://www.va.gov/COMMUNITYCARE/programs/veterans/emergency_care.asp
The Houston VA billing department didn't really help me on this until I got lucky and found the right billing person to explain this. As long it was a true emergency, you are a VA enrolled vet, and you don't have other insurance, they will pay through the Fee Basis. They will pay for SC ER visits if you have private insurance too. Just remember you need to speak about sending the bill to the Fee Basis unit in your area, NOT the Vet Choice, CHAMPUS, Tricare, etc. Be prepared to educate everyone you have dealt with about this. You have up to 2 years to file this claim, but the earlier the better, obviously.
You do not have to get pre-authorization if it is an emergency. If you are discharged from the ER, contact the VA and follow up with your regular VA doctor. Bring the paperwork to make sure it makes it to your file.
If you are admitted from the ER, you have 72 hours to contact the VA to let them determine if you need to move to a VA facility or stay where you are at.
It is complicated, at I had to follow up with the Fee Basis unit to make sure it was being processed. But the second time I was much more prepared and it went smoother because I had the Fee Basis unit address and phone number.