SERVER-110210 added a check to ensure DDL coordinators always resume migrations for collections. We could add a check to ensure the critical section is also released.

One option is to extend the shardingState command to include whether the critical section is taken, and run this command against all shards with data for the given collection.

One caveat is that shardingState is not IDLized, so it's not straightforward to call it from the DDL coordinator.