Ask anyone in the medical profession and you will probably hear this situation is going to last for a while, despite the aspirational goals some may have. The FL surgeon general today issued an
alert warning all residents 65+ to stay at home. Even if the economy open up somewhat and people start to travel more, anyone who is 60+ will (or at least should) think twice before they go anywhere. And that will last for 12-18 months until there is a vaccine. If your renter is 60+ I wouldn't count on them coming in August or any time in 2020.
If you can cancel the reservation and bank the options rather than lose 100% of the rental along with usage and maintenance fees I'd strongly consider it. Be less of an ass to RedWeek than they have been... communicate with them, explain your concerns, and then do what is best for you because they clearly won't.