I was also having an issue trying to book a partner award yesterday. There was a 4-5 hour hold time and the call back option was available. No one called last night...
The partner award number said 10 hours this morning, so I called the MVP reservation line and connected to an amazing agent in 3 minutes. It just so happened they were "partner award trained". Got my booking and ironically another agent called while I was on that call.
I guess you just have to keep trying and as always YMMV and HUCA.