Couchbase Rebalance Hangs C4.1

I was running a swap rebalance of two node, one node was coming in, and one node was leaving for maintenance. This process usually takes ~12 hours with the dataset in each of the buckets. The swap rebalance hung for 3 days. I attempted to stop the rebalance and retry. During the next rebalance I was attempting to only remove a node instead of a swap rebalance. This rebalance operation is also hanging.

Is there anything I can do to resolve this? Right now I cannot add/remove nodes without the rebalance operation becoming stuck for days. I also currently have a bucket with 15/16 nodes active.