OK, This is certainly doable. It may take some persistence, but so long as the records exist...and I suspect they do, at least the "Unit Diary" (that is a Marine Term, but I am certain there is an Air Force equivalent and it may have the same name.
Here is what I would do.
I would draft a request under the Freedom Of Information Act
more info here
Make the request for the "command chronology", the "unit diary" and any other documents that would show the TAD status of members of the 463rd for the year(s) that apply to you. If you can determine the command between PACAF and the 463rd...I suspect it is one of the wings...I would make the request their as well. But start with the request to PACAF.
Make sure you request a waiver of fees. Tell them what your doing...it may help as well.
If the documents exist, you can get them in this manner.
Your medical records may also have some helpful information...I would also request them as well.
Finally, if you have not yet appealed the VA decision, you may consider this as well (though I would do the FIOA request first...it may be on appeal you can use Capt Dana's statement to show that, in fact, you were in country
Please let me know if you have further questions; if so I will do my best to answer them. If not please hit the accept button, its the only way I get credit for my work.