The trip is 7 days away. If there is a big storm coming, then wait till the last minute and they may give you a refund. But, the storm can always go another way and there is no need for you or Mrs. to panic.
You are still lucky with a 7 day cancellation policy. I have seen policies with 1 month or even 2 month cancellation policy on flexible rates.
As for the taste that you are left with Marriott, I don't understand how Marriott is wrong here. Do you think Hilton or Hyatt would have done something different ?? No way!
You are a lifetime Titanium. It's going to take a long time before you will get any status closer to it, but if you still want to go that route for a measly $371 then I guess it's your choice/