Hi,
Deploying Airwave or Aruba central will serve your purpose.
When you create multiple clusters means you are creating clusters in different VLANs hence there will not be any inter IAP communication among the clusters.
If you add all the VCs in the same group in Airwave or Central you can push the same configuration all the VCs and it is the only solution for your deployment.
Hope you got some clarity on this.
Please feel free for any further query on this.