Old paychecks corrupted last March, just noticed today. [Edited]

I have a meticulous 23 year old file. I just ran a file verification, and it noticed dozens of old paychecks were messed up. All the allotments to others accounts (including flex spending) were deleted from the transactions, and the entry in the receiving account registry is now uncategorized. I opened a recent backup, and while the receiving account is no longer blank, it is no longer linked or listed on the paycheck register for the other account. It seems to be an issue especially if the paycheck bank account was closed in quicken. I looked through backups, and the last good one was back in early march.

I tried manually correcting one of the corrupted paychecks, and even if I could fix all the allotment transactions (very time consuming), the transfers to flex spendings weren't working. I think I'd have to delete and recreate each paycheck in it's entirety, which is too much work.

Is there anyway to bulk import 3-4 mos of recent transactions from one quicken file to an older one?