At RD, the stores use the Julian Calender for dating their meats. Today is day 342. If you still have the label, you can compare that number with today's and see if the date was past due. Also, those numbers on the packages reflect when the meats get weighed and put on the shelf. The cases still have the kill dates on them. It is possible for the case to sit a while unsold and then the meats put on the shelf with a current date. Going 5 days out from the date on the meat may be risky. I usually buy my butts for competitons from RD on Wednesdays before the comp.
It is great that they took care of you, no questions asked. I have had great experiences at RD.