Shelby, the price dropping can also be tricky. Just because the website shows the price "from" a lower amount than you paid, that doesn't actually mean all the prices dropped. If you have a larger cabin(s) (which it sounds like you do since you have 5 people) then your cabing price probably did not drop. The price drop is used to fill the "left over" cabins. The larger cabins that hold a hold family sell out quickly.
I did the same thing as you when I saw our cruise price drop. I called them up and that is what they told me. I did get some discount but not as much as I thought I was going to get. But still, it was enough that I was glad I called. In your case it just did work out.
And as far as the C&A membership goes, They don't have record before 97. CCL didn't have our honeymoon cruise in their records and said if we could come up with a ticket stub we could get credit. Luckily, since it was our honeymoon, we still had our Cruise ID card (was called sign and sail then) and a picture of us getting on the ship! You really can't expect them to take everyone's word that they sailed on them in the past (although 97 seems a bit short leashed. CCL has records back to at least 95 and the Honeymoon cruise was in 90.
Carnival Cruise Lines:
Fantasy 90, Celebration 95, Victory 05, Conquest 05, Spirit 6/06, Freedom 6/08, Holiday 7/08, Victory 6/09, Valor 9/09, Dream 6/10, Splendor 8/10,Conquest 8/11,Magic 11/11,Triumph 4/12,Spirit 7/12,Freedom 11/12, Triumph 2/13 - The fire cruise
NCL Dream October 2006, RCCL Mariner OTS June 2007, Celebrity Silhouette 2013