You would not use WFA to monitor the inodes. You can use WFA to increase the inodes by 5%, and use OnCommand Unified Manager (OCUM) to monitor and alert on inode counts. You can also use OCUM to run the WFA workflow with the run script option on the alerts. Just put in the REST call to the WFA workflow. I would suggest that you put a check in your WFA increase inodes command to ensure that you are only increasing inodes if the volume needs it.
I had not seen this technical report before. This is excellent. Thanks for bring this to my attention. I would suggest that the target inode full percentage is well below the near full alert level, so that your workflow is not constantly running. So if your threshold is 90%, whne you hit it you may want to increase inodes to achieve 80% or 70% full.