Anything is possible, but, without documentation of some kind, I'd be a doubting Thomas.
Is the gravestone a VA issue?
If so, you may be able to write/email the VA and ask to please see their documentation, given that you guys are the "official" researchers for this unit!
Barring that, maybe you could find an obituary for the man, which might give some further service details!
Sorry I couldn't help you more! -- Jim H.