I assume (even though it's not clear from your description) that you haven't changed your catalog because of the move ... you are still using the exact same catalog file as before the move. Is that correct?
Is it possible that you accidentally opened the wrong catalog file? How do you know?
Is it possible that this photo shoot was never in one of the collections?
Hi Paige, I simply copied and pasted everything from the old drive onto the new one. Everything is the same, same files, same catalog, same everything.
And it's definitely the same catalog. I only use two LR catalogs. the one on my portable drive (which is missing some collections) and the one on the desktop Mac in work. They have different shoots (and none of the same images appear in both catalogs, they are both clearly delineated), so I know by the photographs in the catalog that I have opened the right one.
As for not having made collections in the first place, I know for sure that this isn't the case because I spent a whole day (for each shoot) processing, editing and sorting these various shoots into carefully designed collections for proofing and then sending to design to print. They couldn't have gone to design without these collections and sorting process being done.