I use the phrase agent orange and other herbicides in my claim statements to cover herbicides in general plus agent orange. It is not necessarily still true about the VA not recognizing AO was used in Thailand. In at least one vet's case the VA acknowledged AO was used in Thailand. This vet won his claim.
A quote from Citation Nr: 1113603 Decision Date: 04/06/11 “In summary, the evidence of record shows that the Veteran served in Thailand during the Vietnam era the period in which VA has acknowledged that Agent Orange was used near the air base perimeter at Udorn AFB.”
“The majority of troops in Thailand during the Vietnam era were stationed at the Royal Thai Air Force Bases of U-Tapao, Ubon, Nakhon Phanom, Udorn,Takhli, Korat, and Don Muang. If a veteran served on one of these air bases as a security policeman, security patrol dog handler, member of a security police squadron, or otherwise served near the air base perimeter, as shown by
MOS (military occupational specialty), performance evaluations, or other
credible evidence, then then herbicide exposure should be acknowledged on a facts found or direct basis. “
Service connection for ischemic cardiomyopathy with congestive heart failure,as due to exposure to herbicides, is granted. The VA didn't mention AO at this point where it granted the claim. It used the word herbicides but they did not deny his claim because he used agent orange exposure in his claim statements.