What would be the best way to extract all the information into a hash so that I can can perform sorts based on Collection, Status, and Modified?

If you want to sort, hashes just get into your way. I'd use a array of arrays, each line represented by a 5 element array: collection id, image count, status, missing, and modified. Depending on what you need to do with the dates, I keep them as is, or convert them to UTC timestamps.