I've... had to adapt to similar circumstances. Separate data sanitization from other problems. Ignore "prioritization" as an activity you can control. Walk up to the first responsible party you can find, and do your best, "Robin Williams as the Genie in Alladin" impression.

poof what do you need?

poof what do you need?

poof what do you need?

Keep going until you end up with a manageable set of problems.