I used it twice - both successfully.

Both times the expired domains were not registered with them.

The interface is antquated and hard to figure out/use.

Also they're expensive.

I guess it worked for me b/c these domain names weren't super popular. But both were good sounding relatively short .com domains.

I've never used the GoDaddy Domain Broker at all ...I've also only ever had bad experiences with GoDaddy

Have you tried using a different registrar to attempt to register the domain?

Don't they usually auction off expiring domains?