I got back to the hotel about 8pm and they had no food or room service for dinner. They had a hot breakfast but it started at 6am. my flight was at 6. Thus like I said, what a waste as the vouchers were not helpful.

As for the meal voucher at another airport, not clue what the "official policy is" but, the good news is the employee at WGP here at STL gladly took my voucher even though it was issued in LAS. She said as long as it was issued within 24 hours she would take it. She did. So, at least I got lunch out of it.