If that doesn't help, I'd say it's time to call Quicken Support on the phone and request help. Let them do a screen share session with you to review a download log file on your computer, to determine the nature of the problem and to figure out how to fix it.
Quicken Support:
Hello @tstepp58
Thank you for reaching out on the community and telling us about your issue. I do apologize for the issue you're having. I'm wondering here if the account connection might need to be refreshed. We might be able to easily do this by going to the edit account screen. I'll leave steps down below on how to do so. Right click on affected accounts and select edit/delete account. Select Online Services > reset account.
Once you've had a chance to try this see if we're able to get connectivity and downloads working again. If not we'll see what we can try next.
Thanks,
Quicken Francisco