By now the Fidelity transaction downloading problems are legendary. Random accounts will miss an entire month's worth of transactions and manually entering them might be too much work. I've discovered a work around - assuming this is a one time problem associated with reauthorizing the accounts.
You could export the CSV from Fidelity and import it into Quicken - in theory - but getting the format right is really tricky. Needs to be perfect and requires a lot of data massaging.
Better solution is to create a new Quicken file. When you connect to Fidelity it will download 2 years worth of data. Then you can export the missing transactions to QIF files that can be imported into your legacy Quicken file.