You can't. I received the following response from Dollar Photo Club:
I want to kindly inform you that DPC accounts auto-delete after a successful transfer of unused Downloads to Adobe accounts. Please be aware that all DPC accounts and DPC account data will not be archived.
Dollar Photo Club Customer Service
I feel completely misled by Adobe, at no point in any of the migration process did it warn you would loose previous purchases, collections, etc.
Yes, Completely misled. BIG FAIL Adobe. I had a library/lightbox in Dollar Photo that took me hours to collect for a book I am working on. Now it's all gone.
I feel your pain. I've lost images that I'd purchased but not downloaded, as well as project collections that I'd spent hours curating.
I complained to Adobe support who told me I should have read Dollar Photo Club FAQs https://www.dollarphotoclub.com/Info/FAQ
However at no point in the "migration" process was there any instructions to do this. Adobe should have published a huge warning prior to deleting DPC accounts.