I also paid a visit to that casino with a full page scan of all six chips (Three 5's and Three 25's) - I believe the following year they came out...

They had the set of 25's but not any of the 5's. I was with a friend and we both bought a couple of sets and I gave a generous tip. Then she said wait a second and called over a supervisor. They checked two different vault area for several minutes and said they couldn't find any 5's. After that I felt really confident they are no longer on the property. They really did look a long time for me...