Even if you can't use it at higher cat properties, there is probably a Cat 1-5 somewhere within a reasonable distance of you.

Do a staycation. I've done that; it can be fun. Or, if you don't want to stay, check in, head home, and then call the front desk the next day to tell them you've checked out. You'd get 1-night credit towards elite status.

Alternatively if you have a Cat 1-5 in the area, you can gift it to someone else by making the ressie under your name, checking in & then giving them the key, & call the next morning to check out. That's assuming you trust whomever you're gifting it to to not trash the room. I had a friend do that. Couldn't use the cert herself, but had a single mom friend w/ young children. Found a local Cat 1-5 property with a pool, checked in & then handed the key to the mom, who enjoyed an overnight stay for free & played w/ the kids in the pool, so a 24-hour mini-vacation for mom & kids. I also did it once for a friend. I was having a large holiday party, already had a friend in the guest bedroom so no extra room, so I made a ressie at the local FFI in my name, checked in, & then gave the key to a friend who drove in from another state to attend the party so she could attend the party but not have a long drive home the same night.

Cheers.